Isolated, regulated, toroidal step down transformer AC power supply design.
Mark
240 VAC in, 9 VAC out.
Phil Allison
"Mark"
> Can anybody point me to a good design of same.
>
> 240 VAC in, 9 VAC out.
** Huh ?
What gobbledegook is this ?
...... Phil
Mike
>
>Can anybody point me to a good design of same.
>
>240 VAC in, 9 VAC out.
The closest thing in terms of a transformer that will be able to
provide 'some' regulation is a ferroresonant one. They were often
used 20 or more years ago but declined more quickly when the UPS
became cheaper.
The yare good at supply regulation but bad for noise and bad for
waveform distortion.
You dont really want to design a ferroresonant in a toroid unless
you want to spend a few weeks getting to grips with the material
properties and all the magnetics calculations and building many
prototypes.
Far better you just get a good SMPS.
But do you really need 9vac for your application or is that to feed
something else that could utilse DC more efficiently ?
or did phil write this so i can practice typing and get even more proficient ;)
--
Regards
Mike
* VK/VL Commodore FuseRails that wont warp or melt with fuse failure indication
and now with auto 10-15 min timer for engine illumination option.
* VN, VP, VR Models with relay holder in progress.
* Twin Tyres to suit most sedans, trikes and motorcycle sidecars
http://niche.iinet.net.au
Rudolf
Rudolf
"Mark" <marknospamp...@dodo.com.au> wrote in message
news:4607c3d8$0$68247$c30e...@lon-reader.news.telstra.net...
Mr.T
"Rudolf" <aus_ele...@rumatech.com> wrote in message
news:130gh02...@corp.supernews.com...
> Uni assignment?
Sounds more like primary school :-)
MrT.
Trevor Wilson
"Mark" <marknospamp...@dodo.com.au> wrote in message
news:4607c3d8$0$68247$c30e...@lon-reader.news.telstra.net...
>
> 240 VAC in, 9 VAC out.
**Why don't you tell us what you are trying to actually do, rather than
telling us what you think you need?
As you may have guessed, your request is difficult to satisfy.
At a minimum, you need to tell us:
* AC or DC
* Maximum and minimum current requirements.
--
Trevor Wilson
www.rageaudio.com.au
--
Posted via a free Usenet account from http://www.teranews.com
jasen
He wants a transformer that regulates.
--
Bye.
Jasen
Mark
9 VAC out, regulated (to 9 VAC) , isolated (from transformer), step down
transformer and AC power supply.
Input fused (at about 2 amps) but I could adapt just about any design to
about that current.
There...but I think I already said it, didn't I ..Let's see?
"Trevor Wilson" <tre...@SPAMBLOCKrageaudio.com.au> wrote in message
news:46082321$0$16301$8826...@free.teranews.com...
>
> "Mark" <marknospamp...@dodo.com.au> wrote in message
> news:4607c3d8$0$68247$c30e...@lon-reader.news.telstra.net...
>> Can anybody point me to a good design of same.
... yes, thats me.
>>
>> 240 VAC in, 9 VAC out.
......ah, I did.
Phil Allison
"Mark"
** BEWARE: Top posting fuckwit on loose !!
> I am trying to build a 240 VAC in (or even 110 VAC in, I really don't
> care) 9 VAC out, regulated (to 9 VAC) , isolated (from transformer), step
> down transformer and AC power supply.
** Seeing as you are a COLOSSAL FUCKING MORON with ZERO
ability to provide a intelligent specification
- just what the FUCK s the application - eh ???
> Input fused (at about 2 amps) but I could adapt just about any design to
> about that current.
** Err - is that 2 amps AC at 240 volts or 120 volts - FUCKWIT ??
> There...but I think I already said it, didn't I ..Let's see?
** This UTTER ASS is either on an overdose of mild altering drugs
- or damn well needs to be.
PISS OFF TROLL !!!!!!!!!!
....... Phil
James
What is the application?
Do you need a regulated 9V RMS Sinewave output? What for?????
James
Phil Allison
"James"
> Do you need a regulated 9V RMS Sinewave output? What for?????
** Forget it - " Mark " is an UTTER MORON with idea whatever of the
meaning of the words he is using.
Must be another ADHD fucked " ladder monkey " or some total FUCKWIT
electrician.
....... Phil
Mark
Within the application, the 9 VAC is rectified, filtered, regulated (to +15
VDC and -15 VDC) and then filtered again.
So the input needs to be regulated to within about (+ or -) 1% 9 VAC.
"Mike" <era...@iinet.net.au> wrote in message
news:46081420$0$7449$5a62...@per-qv1-newsreader-01.iinet.net.au...
Mark
Say please.
"James" <dota...@tpigglet.com.au> wrote in message
news:4609129b$1...@dnews.tpgi.com.au...
Phil Allison
"Mark Isley = Utter FUCKWIT "
> Yes, I really do need 9 VAC for my application.
** BOLLOCKS you do !!
> Within the application, the 9 VAC is rectified, filtered, regulated (to
> +15 VDC and -15 VDC) and then filtered again.
>
> So the input needs to be regulated to within about (+ or -) 1% 9 VAC.
** This TOP POSTING, PITA DAMN FOOL
has just gotta be a ADD fucked cable installer.
What a bloody HOOT !!!!!!!
Lets all keep this CRETIN on the fishing line as long as possible !!
What entertainment !!
.......... Phil
Phil Allison
"Mark Ilsley UTTER FUCKWIT "
** This TOP POSTING, PITA DAMN FOOL
has just gotta be another ADD fucked cable installer !!!!
Just like " Spanky" from Melbourne.
What a bloody HOOT !!!!!!!
Lets all keep this CRETIN on the fishing line as long as possible !!
What top entertainment !!
.......... Phil
Mark
The output of any transformer is only proportional to the voltage of it's
input. AFAIK, anyway.
So if the volts in aren't nominal, nor is the voltage out.
"jasen" <ja...@free.net.nz> wrote in message
news:euapio$dak$2...@jasen.is-a-geek.org...
Phil Allison
> No, I think I want to regulate the output of the transformer.
>
> The output of any transformer is only proportional to the voltage of it's
> input. AFAIK, anyway.
>
> So if the volts in aren't nominal, nor is the voltage out.
** ROTFLMAO - this is absolutely CLASSIC !!!
Mark
"Phil Allison" <phila...@tpg.com.au> wrote in message
news:56shrnF...@mid.individual.net...
Phil Allison
"Mark Ilsley UTTER FUCKWIT "
> Doesn't matter a rats arse to my purpose.
** ROTFLMAO - this is absolutely bloody CLASSIC !!!
This TOP POSTING, PITA DAMN FOOL
has just gotta be another ADD fucked cable installer !!!!
Just like that " Spanky" moron from Melbourne.
What a bloody HOOOT !!!!!!!
James
> Yes, I really do need 9 VAC for my application.
>
> Within the application, the 9 VAC is rectified, filtered, regulated (to
> +15 VDC and -15 VDC) and then filtered again.
>
> So the input needs to be regulated to within about (+ or -) 1% 9 VAC.
*** Thanks...thats the best laugh I've had for ages :)
I'm sure a single 9Vac supply will give you amazingly clean +/-15V rails,
you'd best make sure you get a 500W toroidal though, that'll help..
PMSL
James
Mark
Phil Allison
"Mark Ilsley UTTER FUCKWIT "
> Bullshit
** ROTFLMAO - this is absolutely bloody CLASSIC !!!
This ASININE, TOP POSTING, PITA DAMN FOOL
has just gotta be another ADD fucked cable installer !!!!
Like that " Spanky " complete moron from Melbourne.
What a bloody HOOOT !!!!!!!
Lets all keep the CRETIN on the fishing line as long as possible !!
What top entertainment !!
........ Phil
Mark
"Phil Allison" <phila...@tpg.com.au> wrote in message
news:56smjlF...@mid.individual.net...
Trevor Wilson
>I am trying to build a 240 VAC in (or even 110 VAC in, I really don't care)
>9 VAC out, regulated (to 9 VAC) , isolated (from transformer), step down
>transformer and AC power supply.
>
> Input fused (at about 2 amps) but I could adapt just about any design to
> about that current.
>
> There...but I think I already said it, didn't I ..Let's see?
**WHAT IS THE APPLICATION?
Franc Zabkar
<marknospamp...@dodo.com.au> put finger to keyboard and
composed:
>Yes, I really do need 9 VAC for my application.
>
>Within the application, the 9 VAC is rectified, filtered, regulated (to +15
>VDC and -15 VDC) and then filtered again.
>
>So the input needs to be regulated to within about (+ or -) 1% 9 VAC.
Ask yourself, what is the peak value of a 9 VAC sine wave?
- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
Trevor Wilson
> Incapable of argument.
>
**You have not told us what you are trying to accomplish. You can expect to
suffer derision, until you explain more fully what you are trying to do. A
regulated AC source is difficult to accomplish and usually unnecessary. A
regulated DC source is much easier.
You should also learn about top posting and why it is not a desirable method
of communication.
Rudolf
Rudolf
"Mark" <marknospamp...@dodo.com.au> wrote in message
news:46091546$0$24867$c30e...@pit-reader.telstra.net...
Trevor Wilson
> Why not switch mode?
>
**Because the clown who posted the original request has not revealed why he
needs 9VAC. An SMPS is the worst way to generate AC in low draw
applications.
Phil Allison
"Mark Ilsley UTTER FUCKWIT "
> Incapable of argument.
rebel
>Yes, I really do need 9 VAC for my application.
>
>Within the application, the 9 VAC is rectified, filtered, regulated (to +15
>VDC and -15 VDC) and then filtered again.
which removes the need for any tight regulation of the 9VAC.
>So the input needs to be regulated to within about (+ or -) 1% 9 VAC.
Nah, THAT's bullshit. (Hint: Just think for a moment what effect an increase or
decrease of 0.5V in your AC 9V will have on the REGULATED DC rails.)
Mark
what I have explained is more than sufficient for my purpose.
This isn't rocket science. A minimal design AC source can be achieved with
only ONE component but the output is then at the mercy of the vagaries of
the input voltage.
A better design might involve transformation to a nominal VAC (+/- x%) ,
then rectification and regulation to a nominal DC (+/- y%<x) , filtering and
decoupling and then inversion back to 9 VAC (+/- 1%).
Even Google'sperts should be able to understand that.
"Trevor Wilson" <tre...@SPAMBLOCKrageaudio.com.au> wrote in message
news:46097c67$0$16282$8826...@free.teranews.com...
Phil Allison
"Mark Ilsley UTTER FUCKWIT "
> I am not compelled to explain anything more than what I already have and
> what I have explained is more than sufficient for my purpose.
** Fucking, know nothing IDIOTS like this arrogant PIG do NOT get to
decide what others should accept or believe.
> This isn't rocket science. A minimal design AC source can be achieved with
> only ONE component but the output is then at the mercy of the vagaries of
> the input voltage.
** Funny how every piece of transformer isolated electronic and electrical
equipment made manages to do that, just fine.
But it ain't good enough for this PIG IGNORANT CRETIN !!
> A better design might involve transformation to a nominal VAC (+/- x%) ,
> then rectification and regulation to a nominal DC (+/- y%<x) , filtering
> and decoupling and then inversion back to 9 VAC (+/- 1%).
** ROTFLMAO - this is absolutely bloody CLASSIC !!!
This ASININE, TOP POSTING, AUTISTIC DAMN FOOL
Trevor Wilson
>I am not compelled to explain anything more than what I already have and
>what I have explained is more than sufficient for my purpose.
**You don't have to explain anything. You won't get any help, either.
>
> This isn't rocket science. A minimal design AC source can be achieved with
> only ONE component but the output is then at the mercy of the vagaries of
> the input voltage.
**Correct.
>
> A better design might involve transformation to a nominal VAC (+/- x%) ,
> then rectification and regulation to a nominal DC (+/- y%<x) , filtering
> and decoupling and then inversion back to 9 VAC (+/- 1%).
**Except that it is ridiculously complex and unnecessary. If you would
explain what you are trying to do, then we can help you.
>
> Even Google'sperts should be able to understand that.
**I suggest you Google the following: 'Top poster'.
Mark
application. If I'd had what I wanted, I wouldn't need to ask the question.
What I DO have is an very imperfect NOMINAL 240 VAC, domestic supply, like
everybody else. (actually more imperfect than most, as we live in remote
rural area with many idiosyncrasies in the supply).
I can step down the domestic supply to (nominally) 9 VAC, but it suffers
exactly the same problems as the domestic supply. i.e. the output of the
transformer isn't 9 VAC and isn't a perfect sine wave.
"Franc Zabkar" <fza...@iinternode.on.net> wrote in message
news:vjui03trgj76p2j2p...@4ax.com...
Mark
"Phil Allison" <phila...@tpg.com.au> wrote in message
news:56u4b6F...@mid.individual.net...
Phil Allison
> You are assuming that I had a perfect 9 VAC sine wave input to my
> application.
** No he is not - YOU FUCKING TENTH WIT !!
> What I DO have is an very imperfect NOMINAL 240 VAC, domestic supply, like
> everybody else.
** Then accept the fact that regulating the AC voltage is NOT required.
This ASININE, TOP POSTING, PITA DAMN FOOL
Just gotta be a school boy wanker.
What a bloody HOOOT !!!!!!!
Lets all keep the CRETIN on the fishing line as long as possible !!
What top entertainment !!
....... Phil
Phil Allison
>I see, and you do? (decide what others should accept or believe)
** Fucking, know nothing IDIOTS like this arrogant * PIG *
NEVER get to decide what others should accept or believe.
ROTFLMAO - this is absolutely bloody CLASSIC !!!
This ASININE, TOP POSTING, PITA DAMN FOOL
has just gotta be another ADD fucked PIC programmer !!!!
Mark
or I would have simply purchased one.
The reason WHY I need 9 VAC is because the application needs it and for
reasons that I have already explained.
I may post a schematic of the applications rectification, regulation and
filtering circuit, but I don't think this is necessary.
Most people can understand a statement like "240 VAC in, 9 VAC out",
regulated to a fine tolerance (Say 1%) and isolated from the toroidal step
down transformer.
Back to Goggle now, like a good little boy.
"Trevor Wilson" <tre...@SPAMBLOCKrageaudio.com.au> wrote in message
news:4609a248$0$16407$8826...@free.teranews.com...
Phil Allison
> The reason WHY I need 9 VAC is because the application needs it and for
> reasons that I have already explained.
** YOU have not explained any such thing -
YOU STINKING AUTISTIC LIAR
> I may post a schematic of the applications rectification, regulation and
> filtering circuit, but I don't think this is necessary.
** If it already has a " regulation " circuit, the incoming AC does not
also need regulation
- YOU FUCKING TENTH WIT !!!!!!!!!!!!!!
> Most people can understand a statement like "240 VAC in, 9 VAC out",
> regulated to a fine tolerance (Say 1%) and isolated from the toroidal
> step down transformer.
** It's purest gobbledegook.
Mark
You just accused me of "arrogance" for NOT supplying information (on my
application for the requested design) whilst arguing that your own arrogance
is in fact a power to "decide what others should accept or believe", earned
on the basis of what?
You will claim superior knowledge and experience, but YOUR superior
knowledge experience CAN NOT make ME arrogant, and that is by definition.
Quite to the contrary, it makes your statement look arrogant because you
appear to believe that the power to "decide what others should accept or
believe" is something that can be EARNED by superior knowledge and
experience. That is; it exists AS A RIGHT that can be earned.
No doubt this proposition is TRUE inside THIS newsgroup or it may even be
true inside ALL newsgroups, but it is not true in the wider realm of human
relations or the law, because it is in conflict with the basic tenant of an
individuals free will.
In exercising that free will, I have the right NOT to divulge any
information I consider private (or for any other undisclosed reason) and I
will not let you twist the exercise of that option into an allegation of
arrogance, just as you have attempted to do.
To make that accusation under these specific circumstances is an
abomination.
To infer, by the argument that you have made, that the power to "decide what
others should accept or believe" exists at all as a RIGHT, which can be
earned, is an intrinsically arrogant position to take. It is one that
suppresses all decent.
Can you think of anyone in this newsgroup who suppresses all decent?
"Phil Allison" <phila...@tpg.com.au> wrote in message
news:56u5ltF...@mid.individual.net...
Phil Allison
"Mark Ilsley = UTTER FUCKWIT "
( snip some of the CRAZIEST verbal garbage ever seen on this NG )
** Fucking, know nothing IDIOTS like this arrogant * PIG *
NEVER get to decide what others should accept or believe.
ROTFLMAO - this is absolutely bloody CLASSIC !!!
This ASININE, TOP POSTING, PITA BLOODY FOOL
has just gotta be another ADD fucked PIC programmer !!!!
What a bloody HOOOT & A HALF !!!!!!!
Lets all keep the CRETIN on the fishing line as long as possible !!
What TOP entertainment !!
........ Phil
Mark
childish position to take that I hardly feel deprived of your advice.
You may consider yourself excused of offering and advice.
"Trevor Wilson" <tre...@SPAMBLOCKrageaudio.com.au> wrote in message
news:4609d1a6$0$16313$8826...@free.teranews.com...
Mark
"Phil Allison" <phila...@tpg.com.au> wrote in message
news:56ud2nF...@mid.individual.net...
Phil Allison
"Mark Ilsley = ASININE FUCKWIT "
> Incapable of argument.
Phil Allison
"Mark Ilsley = ASININE FUCKWIT "
> To take exception to the style of postings is such an enormously trivial
> and childish position to take that I hardly feel deprived of your advice.
> Incapable of argument.
( snip some of the CRAZIEST verbal garbage ever seen on this NG )
** Fucking, know nothing IDIOTS like this arrogant * PIG *
NEVER get to decide what others should accept or believe.
ROTFLMAO - this is absolutely bloody CLASSIC !!!
This ASININE, TOP POSTING, PITA BLOODY FOOL
has just gotta be another ADD fucked PIC programmer !!!!
What a bloody HOOOT & A HALF !!!!!!!
Lets all keep the CRETIN on the fishing line as long as possible !!
What TOP entertainment !!
........ Phil
Mark
240 VAC in (nominal) , 9 VAC out (+/- 1%), about 2 amps (but you can make it
10 amps or 1 amp, I don't care), toroidal transformer.
I've already given you sufficient information on the type of circuit it
supplies.
"Trevor Wilson" <tre...@SPAMBLOCKrageaudio.com.au> wrote in message
news:46097308$0$16400$8826...@free.teranews.com...
Two Bob
>
> Lets all keep this CRETIN on the fishing line as long as possible !!
>
> What entertainment !!
You cruel bastard!!
Two Bob
>what I have explained is more than sufficient for my purpose.
YOU are the idiot asking for help here! If you cant give more info, I doubt
you will get more help.
James
"Two Bob" <de...@iprimus.com.au> wrote in message
news:460a1...@news.iprimus.com.au...
But it's true
No only did the OP not say in the beginning what he's really trying to
acheive, but he is off on a completely wrong tangent arguing that he is
correct.
Theres more than one way to skin a cat, but the OP is trying to do it by
blindfolded shoving his fist fair up the cats arsehole and turning it inside
out and hopefully when he takes the blindfold off he'll relise it wasn't a
cat he had in the first place.
OK...well i guess thats a pretty fucked up comparison, but not far off the
Mark.
James
Phil Allison
"James"
"Two Bob"
>>> What a bloody HOOT !!!!!!!
>>>
>>> Lets all keep this CRETIN on the fishing line as long as possible !!
>>>
>>> What entertainment !!
>>
>> You cruel bastard!!
>
> But it's true
>
> No only did the OP not say in the beginning what he's really trying to
> acheive, but he is off on a completely wrong tangent arguing that he is
> correct.
>
> Theres more than one way to skin a cat, but the OP is trying to do it by
> blindfolded shoving his fist fair up the cats arsehole and turning it
> inside out and hopefully when he takes the blindfold off he'll relise it
> wasn't a cat he had in the first place.
>
> OK...well i guess thats a pretty fucked up comparison, but not far off the
> Mark.
** ROTFL
Nice one....
......... Phil
Mark
application can only operate within a tolerance of the regulating IC's
nominal input voltage. The application is using 15 Volt DC regulators
(output), after the bridge rectifier, and can only operate (+/- x%) of 15
volts DC input.
The rectification of (nominally) 9 VAC I understood to result in 18 VDC
(ignoring any small voltage drop across the diodes). So even when the input
voltage is nominal,
the input voltage to the regulating IC's is only within 20% of their nominal
output.
Now what happens if the domestic supply voltage is not nominal?
If the domestic supply comes in at 264 VAC (+10%), the existing linear
regulator now supplies 9.9 VAC to the application, the bridge rectifier
doubles that to 19.8 VAC. The input voltage to the regulating IC's is now
only within 40% of their nominal output!
I monitor the domestic supply and regularly see voltages coming into our
house outside the range of +/- 10%.
One solution, of course, would be to redesign the power supply within the
application's case, including upgrading the regulating IC's input voltage
tolerance to at least 40% of its output, if such an IC can be found!
However space within the applications case would not allow for a toroidal
transformer, which I consider to be the optimum solution for a number of
reasons that I don't need to explain here (or maybe they will insist that I
do that as well?!!), and I have already invested considerable effort (and a
small amount of money) in upgrading the capacitors within the existing
application's power supply and really don't want to loose out on the already
considerable improvements I have made therein.
Quite frankly, I am astounded and reviled that such a simple request has
generated such a vile reaction from this group. I can only assume that it is
because they, like me, were unable to Goggle a suitable design. So as to
maintain their allusion of expertise and so they hide their inability to
self-design a suitable solution, with insults!
I wonder what would happen if I took a simular request for such a simple
thing to another newsgroup, say 'us.electronics', and pointed out to them
that 'aus.electronics' does not have a single contributor who can satisfy
the request. I wonder what they would say. "Too difficult", do you think?
"rebel" <m...@privacy.net> wrote in message
news:9cfj03lh21i2v84iq...@4ax.com...
James
> The way I understand it, the regulation that already occurs within the
> application can only operate within a tolerance of the regulating IC's
> nominal input voltage. The application is using 15 Volt DC regulators
> (output), after the bridge rectifier, and can only operate (+/- x%) of 15
> volts DC input.
>
> The rectification of (nominally) 9 VAC I understood to result in 18 VDC
> (ignoring any small voltage drop across the diodes).
**** Is that right? I would have thought it closer to 12.7v (minus the
forward drop of the diodes), and from one 12Vdc supply how are you going to
achieve +/- 15V. Of course you could use half wave rectification for
+/-12Vdc but if you want to achieve a very stable supply?????
So even when the input
> voltage is nominal,
> the input voltage to the regulating IC's is only within 20% of their
> nominal output.
**** Nope....and an input 20% below the desired output wont work will it?
Assuming (because you wont tell) you are talking about 7815 / 7915
regulators or similar you'd want a good few volts above the output if you
want any sort of regulation.
Mark
idiotic thing to do? Can't really disagree with you there.
I am all too aware of the inherent perils involved in asking for help on any
newsgroup inhabited by the likes of Phil and his 'Phil-o-philes'.
That reason alone is enough to make me cautious of providing any more
information than I need to. My perception of Phil is that the more
information you give him to analize (sic), the deeper your own exposure to
his vile hatred of (just about) everybody on the planet.
"Two Bob" <de...@iprimus.com.au> wrote in message
news:460a1...@news.iprimus.com.au...
Mark
believe it.
Yes, I believe it is half wave rectification. Something above +/- 15VDC,
after rectification of the 9VAC. The schematic does not say, probably it is
assumed knowledge.
I have already employed high ripple current Backgate capacitors after the
regulators, and in coupling the Op-amps, and at quite a few other points
throughout the power supply. Worked a treat in improving the sound.
Yes they are 7815 / 7915 regulators. I remember reading the spec for them
(not that I can find it now).
The case is simply stuffed full of large caps throughout the power supply
and analogue section, and it would simple break my hart to have to pull them
out and start over again (to eliminate the half wave rectification)
Which is why I made my objective the replacement of the 9VAC wall wart power
supply.
Too much to ask?
"James" <dota...@tpigglet.com.au> wrote in message
news:460a2be0$1...@dnews.tpgi.com.au...
Two Bob
>>>
>>> Lets all keep this CRETIN on the fishing line as long as possible !!
>>>
>>> What entertainment !!
>>
>> You cruel bastard!!
>
> But it's true
>
> No only did the OP not say in the beginning what he's really trying to
> acheive, but he is off on a completely wrong tangent arguing that he is
> correct.
>
> Theres more than one way to skin a cat, but the OP is trying to do it by
> blindfolded shoving his fist fair up the cats arsehole and turning it
> inside out and hopefully when he takes the blindfold off he'll relise it
> wasn't a cat he had in the first place.
>
> OK...well i guess thats a pretty fucked up comparison, but not far off the
> Mark.
LOL
After reading the rest of the thread, all I can say is "Go for it Phil"!!
Poxy
> "Mark" <marknospamp...@dodo.com.au> wrote in message
> news:460a28af$0$24860$c30e...@pit-reader.telstra.net...
> > The way I understand it, the regulation that already occurs within the
> > application can only operate within a tolerance of the regulating IC's
> > nominal input voltage. The application is using 15 Volt DC regulators
> > (output), after the bridge rectifier, and can only operate (+/- x%) of
15
> > volts DC input.
A common 7815 regulator will put out a stable 15v for input voltages between
17.5v and 30v. That's plenty of headroom for any overvoltage situation on
the mains side.
Mark
A regulated circuit can benefit from the pre-regulation of the incoming AC.
Specifically, where the incoming AC strays outside the operating range of
the regulating IC's output voltage, the benefits may include, for example,
not having any blue smoke emanating from the unit.
Regulating IC's aren't expensive, so it seems a common sense precaution to
make, particularly where other work, (the replacement of the existing
wall-wart with a toroidal step down transformer) is envisaged. Which is
EXACTLY what I originally indicated.
Hey Philthy, we miss you over at 'aus.hifi'.
"Phil Allison" <phila...@tpg.com.au> wrote in message
news:56u72fF...@mid.individual.net...
Mark
remember.
Show me your spec please. I remember reading something less (much less), but
I haven't got it in front of me.
I am sure that you can appreciate that since I am replacing a wall-wart
power supply with a toroidal step down transformer, the cost of an
additional IC regulator is rather trivial when compared to the cost of the
rest of the project.
It may turn out that the particular IC's that I have in place don't regulate
to a 30 VDC input, either by design or circumstance.
The application certainly occasionally behaves erratically (on/off clipping
of output) and I know that this behaviour coincides with over voltage supply
problems. I monitor the domestic supply using software which queries and
records data from an UPS. So there is no doubt about the cause. 100%
correlation.
If the cost of certainty (solving the problem by putting in a bigger, better
IC regulator) is about 10 bucks (and, apparently, putting up with a few
arse-clowns because I was foolish enough to ask for help @
'aus.electronics') then I can go the extra distance, I guess.
"Poxy" <p...@poxymail.com> wrote in message
news:MIqOh.2795$M.1...@news-server.bigpond.net.au...
Mark
"James" <dota...@tpigglet.com.au> wrote in message
news:460a...@dnews.tpgi.com.au...
Mark
that I gave to them, when I asked something from them, or I will not submit
to their demands.
If the cost of this personal policy is not receiving the help I requested
then I would much prefer not to receive it. The price of self-respect is
inestimable. Is that too difficult for you to understand?
The direct inference from your comments here and elsewhere on this thread is
that you expect me (and possibly all newcomers) to submit to this bulling in
order to receive the help that they need.
That is the definitive behaviour of a 'Phil-o-phile'.
You are a 'Phil-o-phile' and I expect nothing from you.
"Two Bob" <de...@iprimus.com.au> wrote in message
news:460a3...@news.iprimus.com.au...
Mark
who then goes on to immediately infer that the power to "get to decide what
others should accept or believe" is a right that; a) Exists. b) Could be
earned, granted or perhaps even shared with others, at the decreation of the
right-holder(s).
Cognizant with this position is the logical assertion that the entry fee to
this exclusive club of 'deciders', as you so called them, is the
demonstration of superior knowledge or experience.
Perhaps not coincidently, I suggest that this hypothesis serves as a
tentative STRUCTURAL description for the organisation of?
...'Phil-o-philes'.
Just for my future edification, can anyone offer me a list of possible
members of the 'club of deciders' at 'aus.electronics'. To the uninitiated
contributor at this newsgroup, this would be an invaluable aid to 'fitting
in'.
Know what I mean?
"Phil Allison" <phila...@tpg.com.au> wrote in message
news:56uf4lF...@mid.individual.net...
Alex Gibson
> Well, according to the schematic it is +/- 15VDC after regulation. And I
> believe it.
>
> Yes, I believe it is half wave rectification. Something above +/- 15VDC,
> after rectification of the 9VAC. The schematic does not say, probably it
> is assumed knowledge.
>
> I have already employed high ripple current Backgate capacitors after the
> regulators, and in coupling the Op-amps, and at quite a few other points
> throughout the power supply. Worked a treat in improving the sound.
>
> Yes they are 7815 / 7915 regulators. I remember reading the spec for them
> (not that I can find it now).
>
> The case is simply stuffed full of large caps throughout the power supply
> and analogue section, and it would simple break my hart to have to pull
> them out and start over again (to eliminate the half wave rectification)
>
> Which is why I made my objective the replacement of the 9VAC wall wart
> power supply.
>
> Too much to ask?
Why ?
If it works don't fix it.
If you need dual rails, thats the usual way to do it.
Half wave rectifier from a centre tapped transformer + linear regs.
Nice and cheap.
Alex
rebel
wrote:
>The way I understand it, the regulation that already occurs within the
>application can only operate within a tolerance of the regulating IC's
>nominal input voltage.
Not exactly. There are precious few (if any) three-terminal regulators that
won't handle a 30V or 40V input for 15V out. Your configuration is far more
likely to suffer from UNDER-voltage out of the rectifier arrangement.
>The application is using 15 Volt DC regulators
>(output), after the bridge rectifier, and can only operate (+/- x%) of 15
>volts DC input.
No, three-terminal regs don't work that way. Get a datasheet for a 7815 or 7915
and have a good read of the input voltage range. Let's see, 7815 ...
Dropout voltage (typical): 2.0V
Vin (max): 35V
So a 7815 will regulate as long as the input voltage doesn't exceed 35V or drop
below 17V on the troughs of the input waveform.
>The rectification of (nominally) 9 VAC I understood to result in 18 VDC
>(ignoring any small voltage drop across the diodes).
It may be small but it isn't insignificant. And I don't like your rectification
theory either.
> So even when the input voltage is nominal,
>the input voltage to the regulating IC's is only within 20% of their nominal
>output.
The Vin-Vout capability of (again, 3-terminal) regs is a spec figure you'll find
on the data sheet, often termed drop-out voltage. See above. It's *not* a
percentage thing. If your input drops (even on transients) to 2V above your 15V
output, or less, you will lose regulation. 20% of 15V is 3V which - if your
rectifier is really providing 18V DC - is barely enough, and ripple at any sort
of load will kill you.
>Now what happens if the domestic supply voltage is not nominal?
>
>If the domestic supply comes in at 264 VAC (+10%), the existing linear
>regulator
I think you mean transformer
> now supplies 9.9 VAC to the application, the bridge rectifier
>doubles that to 19.8 VAC.
I don't like your rectifier model, but let's ignore that for the moment.
> The input voltage to the regulating IC's is now
>only within 40% of their nominal output!
They should be happier. Warmer, but happier. Realise also that the output of
your rectifier system will show significant ripple as load current increases,
and those dips threaten the very regulation those regulators are trying to
provide.
Your concept of how regulators work is more than a worry. And IMNSHO it
unperpins all your problems.
>I monitor the domestic supply and regularly see voltages coming into our
>house outside the range of +/- 10%.
>
>One solution, of course, would be to redesign the power supply within the
>application's case, including upgrading the regulating IC's input voltage
>tolerance to at least 40% of its output, if such an IC can be found!
Read the data sheet, and understand what a 3-terminal reg does.
>However space within the applications case would not allow for a toroidal
>transformer, which I consider to be the optimum solution for a number of
>reasons that I don't need to explain here (or maybe they will insist that I
>do that as well?!!), and I have already invested considerable effort (and a
>small amount of money) in upgrading the capacitors within the existing
>application's power supply and really don't want to loose out on the already
>considerable improvements I have made therein.
Throwing bulk cap around will obviously improve (aka mask) the regulation
situation. But it is masking the symptoms, not fixing the cause.
You mentioned in another post that this is accompanying a move from a 9VAC
wall-wart to a hopefully better transformer.
What I sincerely suggest you do is (in order):
(a) Get the data sheets for the regulators that you are using. If they aren't
7815/7915 then I feel compelled to ask why not.
(b) Measure (even with a DMM) the input voltage to the regulator(s) and
convince yourself that you have enough headroom to operate properly. Better
still if you check the ripple with a CRO too. Even better, get a CRO and watch
the waveform applied to the input of the regulators, and load/unload teh system
so that the ripple can be quantified.
(c) Check whether the regs are running hot to touch.
(d) Try a 12VAC wall wart, unless the DCin to the regs is already 23V or more.
>Quite frankly, I am astounded and reviled that such a simple request has
>generated such a vile reaction from this group. I can only assume that it is
>because they, like me, were unable to Goggle a suitable design. So as to
>maintain their allusion of expertise and so they hide their inability to
>self-design a suitable solution, with insults!
Quite frankly, I am astounded that you seemed to think that these problems are
best solved by shooting for an (affordable) transformer offering 1% line
regulation. If that were the best solution, such transformers would abound, and
Google would have turned up a mutitude of solutions for you. Rather, the
solution to such requirements have been de rigeur for decades, earning the tag
classical.
Your request was further obfuscated - and the task of steering you towards a
sound and achievable/affordable solution - by giving more of your planned
solution than the description of the application and the problem.
>I wonder what would happen if I took a simular request for such a simple
>thing to another newsgroup, say 'us.electronics', and pointed out to them
>that 'aus.electronics' does not have a single contributor who can satisfy
>the request. I wonder what they would say. "Too difficult", do you think?
No, they'd wonder why you were searching for an electronic sledgehammer.
Whether you choose to follow my, or anyone else's, suggestions is up to you.
But among the flaming, you have been given more than enough leads to achieve a
sensible outcome.
And please don't top-post
--
Bob Parker
> news:460a3520$0$24857$c30e...@pit-reader.telstra.net...
>>
>> regulators,
Ummm, can someone enlighten me as to what a Backgate capacitor
is...? I did the obligatory Google searching but didn't find anything
very informative.
Bob
Alex Gibson
> It certainly would be reassuring to know that I have more head room than I
> remember.
>
> Show me your spec please. I remember reading something less (much less),
> but I haven't got it in front of me.
Maybe if you bothered looking at the datasheets for the devices you are
using.
Usual first step before using a device is read the datasheet or manual.
For a 7815
http://www.fairchildsemi.com/pf/LM/LM7815.html
http://www.national.com/ds/LM/LM340.pdf
input range is 17.5V to 30V DC.
Need minimum of 17.5 to get regulated 15V output.
Using a simple AC circuit + bridge rectifier or diodes + linear reg is a lot
cheaper and simpler than mucking around with AC regulation.
May not be the most energy efficient circuit but is simple and easy to fault
find.
Also a less noise than any switchmode or boost/buck converter circuit.
Alex
Mark
Maybe the 'value' he refers to is the peak value of current under load, or
was he talking about the peak positive value and peak negative value of the
voltage (?) in the sine wave, which is what I thought him to mean.
I suppose only he can say what he meant.
"Phil Allison" <phila...@tpg.com.au> wrote in message
news:56u5guF...@mid.individual.net...
> "Mark Ilsley = UTTER FUCKWIT "
>
>
>
>> You are assuming that I had a perfect 9 VAC sine wave input to my
>> application.
>
>
> ** No he is not - YOU FUCKING TENTH WIT !!
>
>
>
>> What I DO have is an very imperfect NOMINAL 240 VAC, domestic supply,
>> like everybody else.
>
>
> ** Then accept the fact that regulating the AC voltage is NOT required.
>
>
> This ASININE, TOP POSTING, PITA DAMN FOOL
>
> Just gotta be a school boy wanker.
>
> What a bloody HOOOT !!!!!!!
>
> Lets all keep the CRETIN on the fishing line as long as possible !!
>
> What top entertainment !!
>
>
>
> ....... Phil
>
>
>
>
Poxy
"Bob Parker" <bobp.de...@bluebottle.com> wrote in message
news:460a5bc0$0$7400$5a62...@per-qv1-newsreader-01.iinet.net.au...
My guess? They're "acoustically transparent" and cost a bomb.
Mark
"Bob Parker" <bobp.de...@bluebottle.com> wrote in message
news:460a5bc0$0$7400$5a62...@per-qv1-newsreader-01.iinet.net.au...
dmm
>Can anybody point me to a good design of same.
>
>240 VAC in, 9 VAC out.
>
Just about any audio amplifier and a sine wave generator will do the job.
What exactly is it that you want to achieve?
Poxy
> It certainly would be reassuring to know that I have more head room than I
> remember.
>
> Show me your spec please. I remember reading something less (much less),
but
> I haven't got it in front of me.
You haven't tried Googling 7815 datasheet?
I think you also need to revise basic power supply design, in particular,
the manner in which regulators work, and the recommended filtering
configuration on the input and output of the regulator.
As others have pointed out, it may well be that your AC power supply isn't
supplying adequate voltage to prevent one or both of the regulators dropping
out under load.
> I am sure that you can appreciate that since I am replacing a wall-wart
> power supply with a toroidal step down transformer, the cost of an
> additional IC regulator is rather trivial when compared to the cost of the
> rest of the project.
No, I don't appreciate that perspective, because it isn't the most obvious
answer to what you've explained. The fact that you believe a regulator
requires an input voltage within some percentage, either postive or
negative, of the output voltage underpins where your thinking has gone
wrong.
You're also convinced the issue is overvoltage, whereas looking at the whole
system, it looks more like the AC transformer isn't putting out enough
voltage. It could well be that another plug pack with a higer output voltage
and suitable current rating would solve the problem, or it could be that the
plugpack you have is a dud.
> The application certainly occasionally behaves erratically (on/off
clipping
> of output) and I know that this behaviour coincides with over voltage
supply
> problems. I monitor the domestic supply using software which queries and
> records data from an UPS. So there is no doubt about the cause. 100%
> correlation.
Possibly, but there's a much more obvious answer that does a better job of
explaining your problem.
> If the cost of certainty (solving the problem by putting in a bigger,
better
> IC regulator) is about 10 bucks (and, apparently, putting up with a few
> arse-clowns because I was foolish enough to ask for help @
> 'aus.electronics') then I can go the extra distance, I guess.
Perhaps if you had stated from the start that your plugpack-powered preamp
(I'm guessing) is exhibiting distortion and that you suspect a power supply
issue, you might have gotten more rigorous and methodical advice. The next
question would have been what are the regulators, what voltage is appearing
at the input of each regulator, and are they getting hot.
That said, *nobody* deserves the kind of response and language that a
certain person has used in this thread.
Also, if you are asking for help and advice, it's polite to observe accepted
etiquette - that inlcudes refraining from top-posting particularly if asked
not to.
Bob Parker
Correct (see my other post with the info). Just the thing for
transparently filtering 100Hz ripple.
Bob
Bob Parker
> *Black Gate. I don't know how I can live with myself.
>
>
> "Bob Parker" <bobp.de...@bluebottle.com> wrote in message
> news:460a5bc0$0$7400$5a62...@per-qv1-newsreader-01.iinet.net.au...
>>> "Mark" <marknospamp...@dodo.com.au> wrote in message
>>> news:460a3520$0$24857$c30e...@pit-reader.telstra.net...
>>>> I have already employed high ripple current Backgate capacitors after
>>>> the regulators,
How could I not have realized that's what you meant?
For everyone's edification, from
http://www.hificollective.co.uk/components/black_gate_caps.html ....
Black Gate Electrolytic Capacitors
----------------------------------
There are very few audio parts that promise a guaranteed improvement
when replacing practically any other part, but this is what the BLACK
GATE™ capacitors actually do. Exchanging any electrolytic capacitor
anywhere in the circuit of a CD-player, amplifier or in the crossover of
a speaker will greatly improve sound quality. BLACK GATE™ are recognised
worldwide as the best electrolytics capacitors money can buy.
Phil Allison
"Poxy"
> That said, *nobody* deserves the kind of response and language that a
> certain person has used in this thread.
** Oh yes they do - plus a whole lot more besides.
The likes of " Mark Ilsley " are among the most vile creatures infesting
the face of the earth.
A bullet to the forehead would be far too kind a fate for an individual who
has continually tortured so many innocents for so many years.
No surprise that a prick like you is in sympathy with this oxygen thief.
Cos YOU are another one of the same fucking pukes.
....... Phil
Mark
inside the application.
I don't want to alter the application, at all and I would prefer not even to
discuss it.
I would like to point out that my original question deliberately had NOTHING
to do with the application. The easiest way to eliminate the unwanted
discussion is to not provide information on the application.
So, WE are stuck with AC as an input to the application. I wanted to
eliminate the AC/AC wall-wart transformer (which uses an Iron core
transformer) and replace if with a Toroidal core transformer.
Do I need to justify this choice as well?
"Alex Gibson" <ne...@alxx.org> wrote in message
news:56v3u8F...@mid.individual.net...
Phil Allison
" Mark Ilsley = UTTER FUCKING LIAR "
> BUT I DON'T want to eliminate the half wave rectifier!!! It is
> pre-existing inside the application.
** Hey - you asinine CUNT.
YOU do not have the tiniest clue what a " half wave rectifier " is.
Cos you are a lying, fucking ass.
> I don't want to alter the application, at all and I would prefer not even
> to discuss it.
>
> I would like to point out that my original question deliberately had
> NOTHING to do with the application. The easiest way to eliminate the
> unwanted discussion is to not provide information on the application.
>
** It don't matter a RAT'S FUCK what some vile, brain dead, autistic,
delusional CUNTHEAD might be psychotic enough to believe is not necessary
for other people to know.
When it is.
> So, WE are stuck with AC as an input to the application. I wanted to
> eliminate the AC/AC wall-wart transformer (which uses an Iron core
> transformer) and replace if with a Toroidal core transformer.
>
** Got news for YOU - CUNT !!
Toroidal mains transformers have all got " IRON " cores too.
GOSS to be precise.
> Do I need to justify this choice as well?
** Absofuckinglutely !!!!!!!!!!!!!!!
Cos toroidal mains transformers are * NOT LEGALLY APPROVED * as SAFE
for the same applications that plug packs ALL are.
Cos they have no better voltage regulation than plug packs of the same VA
rating - most are worse.
And because NO common AC supply transformer regulates against mains
variations.
Because they do not need to !!!!!!!!!!!!!!
THIS is absolutely bloody CLASSIC !!!
This ASININE, TOP POSTING, PITA DAMN FOOL
has just gotta be another ADD fucked audiophool MORON !!
What a bloody HOOOT !!!!!!!
Lets all keep the CRETIN on the fishing line as long as possible !!
What top entertainment !!
........ Phil
Mark
1) "7815" gives about 4 million hits on Goggle.
2) I asked for the help a little over 48 hours ago, and since that time I
have had to suffer about 30 attacks, but NO HELP what-so-ever.
3) I have a family and one particular dependant who is bed ridden.
What did you expect from me?
"Poxy" <p...@poxymail.com> wrote in message
news:mHtOh.2873$M.1...@news-server.bigpond.net.au...
Bob Parker
> Three things:
>
> 1) "7815" gives about 4 million hits on Goggle.
>
> 2) I asked for the help a little over 48 hours ago, and since that time I
> have had to suffer about 30 attacks, but NO HELP what-so-ever.
>
> 3) I have a family and one particular dependant who is bed ridden.
>
> What did you expect from me?
I haven't been paying close attention to this thread, but no item of
audio (or any other mains-powered) equipment which is working properly
is going to be affected by tiny mains voltage variations. If that's
happening, then it's faulty and it should be looked at and repaired by
someone who understands electronics.
All this talk about toroidal transformers, voltage regulators and
acoustically transparent capacitors seems irrelevant, or did I miss
something by not reading everything?
BTW: 'wall wart' is another Americanism creeping into the Australian
vernacular. I suppose one day we'll have 117V 60Hz mains and beoome the
51st or 52nd or whatever it is state of the USA.
Poxy
>
> "Poxy"
>
> > That said, *nobody* deserves the kind of response and language that a
> > certain person has used in this thread.
>
>
>
> ** Oh yes they do - plus a whole lot more besides.
>
> The likes of " Mark Ilsley " are among the most vile creatures infesting
> the face of the earth.
Oh be nice and go to bed Phil.
Poxy
> Three things:
>
> 1) "7815" gives about 4 million hits on Goggle.
A Google on 7815 datasheet gets you the answer - very first result.
Secondly, it isn't really about the specific attributes of the 7815 - as
soon as you've had anything to do with power supplies, you get familiar with
some very basic rules, one of which is that you need 2-3v extra at the input
of a regulator for it to work - that applies to 7805s, 7812s etc.
> 2) I asked for the help a little over 48 hours ago, and since that time I
> have had to suffer about 30 attacks, but NO HELP what-so-ever.
That's because you didn't provide sufficient information from the start, and
I don't mean to be rude, but what you initially suggested was absurd - it
was. Really. It might have made sense to you given your background, but to
anyone with experience in almost any field of electronics, regulated power
supplies are such common and basic things that we pretty much all understand
how they work, the issues that arise and how to deal with them.
What you said initially was the equivalent of saying: "How can I synthesise
better fuel?" Then you say "I've purchased lots of really expensive fuel
filters, which are black by the way - that hasn't helped, so I clealry need
to re-sythesise my existing fuel to make it more consistent".
Everyone laughs at you. Particulalry when we discover how much those fuel
filters cost.
Finally you say: "My engine is running badly, I think it's a fuel problem".
And if you were really being straight-up with us, you'd also say "Actually,
I built the engine, it's running badly, does anyone want to buy some really
good fuel filters?"
> 3) I have a family and one particular dependant who is bed ridden.
>
> What did you expect from me?
I'm honestly sorry to hear that one of your family is ill, and I'm also
sorry that you've had to endure such unpleasant language and abuse, but it's
Usenet, a base level of mocking and general derision comes with the
protocol.
If you really want help, rather than seeking confirmation of your various
theories, just tell us what the actualy device is, who designed and built
it, what the voltage is at the input of the regulators is and what caps you
have on each side of the regulator.
Oh, and maybe refrain from top-posting - it really does annoy people.
Phil Allison
> That said, *nobody* deserves the kind of response and language that a
> certain person has used in this thread.
** Oh yes they do - plus a whole fucking lot more besides.
The likes of " Mark Ilsley " are among the most VILE parasites infesting
the face of the earth.
A bullet to the forehead would be far too kind a fate for this cretin who,
due
to his manifest, congenital mental defects has continually tortured the
lives of
so many innocents for so many years.
No surprise that a * total prick * like POXY is in sympathy with this
utterly disgusting oxygen thief.
Cos POXY is another of the same sub human species.
Peeeeeuuuukeeeeeee !!
....... Phil
Mark
described about the applications circuit is consistent with that conclusion.
A voltage doubling design CAN BE a variant of the simple half wave rectifier
design.
...You didn't know that!!?
It now appears that I have over estimated your claim to the 'right' to
decide. You see, I knew something that you didn't.
Bet then again, maybe you're just having an 'off day'?
No, it couldn't be that. That would ascribe to you the human characteristic
of fallibility. ...And you are infallible, right?
I didn't (and don't) claim any expertise in the area of electronics, but you
label ME arrogant and YOURSELF as infallible.
...and then you DON'T KNOW that a voltage doubling design CAN BE a variant
of the simple half wave rectifier!!? Fuck me, what am I dealing with here?
And another thing, Phil: I don't DECIDE what is 'necessary' for other people
to 'know'.
I DECIDE what I will or won't TELL them about my project. That is my RIGHT
as a human being. It is called exercising my 'free will'.
Some of what I DECIDE not to tell others, MAY or MAY NOT be 'necessary' for
their understanding, but I can't and don't decide what is or what isn't
'necessary' for their understanding. Only THEY can do that and no doubt they
do.
You see, this very distinction, or rather your total failure to grasp that
distinction, is at the hart of your belief that some people "get to decide
what others should accept or believe" whilst others "NEVER" do.
You see, you have assigned this power AS IF it EXISTED as a right, to be
held by some but not others, presumably on the basis of knowledge and
experience. Nobody holds that power, for it does not exist, IN TOTO. You can
not decide for others what those others "should accept or believe", period.
The power does NOT EXIST, at all, period.
The basic human tenant of "free will" excludes all possibility that it CAN
exist as a power. Why?
Because you can not FORCE anyone to BELIEVE anything. Quite clearly, you
believe that these 'deciders' as you called them, can do just that.
Indeed, you have said as much, about dozen times, in this very forum.
And another thing, you petty child. Toroidal core transformers are classed
and commonly refered to as 'Air Core' transformers. In this case, the 'Air'
refers to the hole in the middle (i.e in the 'Core') THAT YOU CAN SEE.
Iron cores (or Steel Core) transformers commonly have a hole in the middle
(of the Iron) as well, but you can't see it.
You can google all day Phil, but you still didn't know that a voltage
doubling rectifier is variant of the simple half wave rectifier.
Nar, nar, nan-nar-nar.
Child.
"Phil Allison" <phila...@tpg.com.au> wrote in message
news:56va6nF...@mid.individual.net...
Phil Allison
" Mark Ilsley = AUTISTIC FUCKING IDIOT "
** Oh boy, I see this one - but I dooaaan believe it ........
> And another thing, you petty child. Toroidal core transformers are classed
> and commonly refered to as 'Air Core' transformers. In this case, the
> 'Air' refers to the hole in the middle (i.e in the 'Core') THAT YOU CAN
> SEE.
** Well - bugger me.
I never woulda thought of that one in a thousand years.
And I'm still not thinking it.
> Iron cores (or Steel Core) transformers commonly have a hole in the middle
> (of the Iron) as well, but you can't see it.
** Gotta be real careful of those invisible holes in transformers.
Might stick your foot right in one..........
Like in some pile of smelly bovine excreta.
Dropped by Mark Ilsley, the congenital, donkey brained cunthead.
Heeee haawww, heeee haawwww
....... Phil
Bob Parker
Like him or not, Phil knows his stuff. I'm not taking sides, but
you've just demonstrated how little you know about electronics and
electrical/magnetic theory and Phil's going to pounce on it.
And as I said before, if mains voltage changes are affecting your
secret audiophile preamp or whatever it is, it is *faulty* and needs to
be repaired not redesigned.
Bob
Phil Allison
"Bob Parker"
>
> Like him or not, Phil knows his stuff. I'm not taking sides, but you've
> just demonstrated how little you know about electronics and
> electrical/magnetic theory and Phil's going to pounce on it.
** Meeeeeeoooooowwwwww ........
........ Phil
Mark
me.
Quite fairly, I knew the extra voltage was required. It was never in doubt.
What was in doubt (and still is, in doubt) is HOW much over voltage my
particular IC can withstand and still continue to provide the required
voltage output at the peak current, under the load.
It's observed behaviour strongly indicates that it can not. (very strongly).
So maybe I have a faulty regulator. So maybe the faulty regulator was cased
by persistent voltage over loads in my domestic supply. Or, maybe the
particular 7815 /7915 pair that I have does not have the same spec.
Either way, the cheapest solution is sounding like I should exchange the
7815 /7915 pair, for a pair that DOES have that 30V spec. and in so doing,
eliminate the possible cause of the observed clipping during voltage
overloads.
Yes, whether you meant to or not, you are being rude to suggest that I
deserved this treatment BECAUSE my question was to simple.
Is that explanation the 'official fiction', or just the one you offer?
Also, I take umbrage (offence, to you) at your trite analogy. It isn't an
accurate portrayal of what happened or my actions or my motivations or my
attitude. I would welcome a point-by-point comparison of your analogy and my
behaviour.
An interesting aside is the cost of the Black Gates. I was and probably sill
can buy them at about the same price for comparable caps in the Rubycon
ZL/ZLH/ZA series sourced from Farnellinone (so ok, they are arse bandits as
well!)
Here is the link. http://www.kyoto-electro.com/nx.html
For example, a 6.3v, 47uF, NX Hi-Q (one of the very best caps BG makes) is
listed at $2.19. The same ZA sells for $1.50. For the extra dollar I'd have
the NX Hi-Q EVERY TIME. On the other hand, for the budget conscious amongst
you, the STD GB sells for $1.77.
Do the comparisons yourself, son, and you will find that the prices I PAY
for Black Gates are not laughable. You may find exceptions but in general,
they are comparable with the best Rubycon has to offer. If I find a price I
don't like, I go elsewhere.
Your PRESUMPTION that I must pay too much for my Black Gates is based on
what? An ASSUMPTION that I pay foolish prices. That is both insulting AND
ignorant (of how cheaply Black Gates can be purchased).
I also take umberage to your allegation that I am not "being straight-up
with [this group]".
You reckon that if i was being honest I would say "Actually, I built the
engine, it's running badly, does anyone want to buy some really good fuel
filters?" Here is why I wouldn't say such a thing:
a) I didn't build the application, I modified it.
b) It isn't running badly (under nominal conditions), it sounds superb.
c) I am not SELLING anything.
Reguarding the remainder of your comments, I feel compeled to correct you on
the following matters.
a) My bed ridden family member is not ill, he is handicapped and has been so
since birth. Not all handicaps are as a result of illness.
b) I do not feel compelled to accept the derision, no matter how common it
may have been in the past. I expect to be treated in exactly the same manner
that I treat others. I can't stop people from deriding me for on any
particular subject, but I don't have to ACCEPT it, period. You would
probably be amused to learn that it is actually possible to offer assistance
to others without assuming a condescending manner or belittling the
recipient. A skill you haven't acquired yet.
c) I choose to exercise my 'free-will' and I choose what I divulge to others
about me, my family, my interests AND my endeavours. If that personal policy
costs me some useful assistance then it is MY PREROGATIVE to assess the
opportunity cost and weigh it against the loss of the privacy of my
endeavours. That is my assesment to make and mine alone. You can not tell me
what I MUST tell people.
d) Regarding your objection to my posting style, it is frivolous. I can find
or fabricate just as many objections to bottom posting, or to Phils style of
endless analizing (sic).
I could just as easily object to your abhorrent spelling, not because I wish
to seize an opportunity to deride your intelligence but because it makes the
task of my own spell checker that much more tiresome.
I think that covers it for now
I look forward to our point-by-point comparison of your analogy with my
behaviour. I can't find many comparisons at all. Do you do this often? (that
is: make up stupid analogies that just don't work).
>
> Oh, and maybe refrain from top-posting - it really does annoy people.
"Poxy" <p...@poxymail.com> wrote in message
news:ZfvOh.2902$M....@news-server.bigpond.net.au...
>
> "Mark" <marknospamp...@dodo.com.au> wrote in message
> news:460a7519$0$24869$c30e...@pit-reader.telstra.net...
>> Three things:
>>
>> 1) "7815" gives about 4 million hits on Goggle.
>
> A Google on 7815 datasheet gets you the answer - very first result.
> Secondly, it isn't really about the specific attributes of the 7815 - as
> soon as you've had anything to do with power supplies, you get familiar
> with
> some very basic rules, one of which is that you need 2-3v extra at the
> input
> of a regulator for it to work - that applies to 7805s, 7812s etc.
>
>> 2) I asked for the help a little over 48 hours ago, and since that time I
>> have had to suffer about 30 attacks, but NO HELP what-so-ever.
>
> That's because you didn't provide sufficient information from the start,
> and
> I don't mean to be rude, but what you initially suggested was absurd - it
> was. Really. It might have made sense to you given your background, but to
> anyone with experience in almost any field of electronics, regulated power
> supplies are such common and basic things that we pretty much all
> understand
> how they work, the issues that arise and how to deal with them.
>
> What you said initially was the equivalent of saying: "How can I
> synthesise
> better fuel?" Then you say "I've purchased lots of really expensive fuel
> filters, which are black by the way - that hasn't helped, so I clearly
Mark
Phil.
Bob is a Pussy.
But you still didn't know that a voltage doubling rectifier CAN BE a
variant of the simple half wave rectifier.
Nar, nar, nan-nar-nar!!!
Boy, this is fun isn't it.
"Phil Allison" <phila...@tpg.com.au> wrote in message
news:56vi6bF...@mid.individual.net...
Mark
"dmm" <dmmilne...@ozemail.com.au> wrote in message
news:dgpk03dblhp6f595b...@4ax.com...
Mark
proven.
Philthy could get out of it by claiming that he has made a simple mistake
but I mean how likely is that event really? Huh???
Phil REALLY believes he is infallible and so would be incapable if making
such an admission.
That is why he is the 'decider' of "what others should accept or believe"
He has inferred as much, in this very forum, about a dozen times or so.
"Bob Parker" <bobp.de...@bluebottle.com> wrote in message
news:460a915d$0$7399$5a62...@per-qv1-newsreader-01.iinet.net.au...
Bob Parker
> That is the first thing that you've said in here that I actually agree with
> Phil.
>
> Bob is a Pussy.
>
> But you still didn't know that a voltage doubling rectifier CAN BE a
> variant of the simple half wave rectifier.
>
> Nar, nar, nan-nar-nar!!!
>
> Boy, this is fun isn't it.
You really don't get it, do you Mark? It's all over your head like a
tent. I felt a bit sorry fot you and tried to steer you in the right
direction, but you won't listen.
Bob (the one Phil's comment was aimed at - you think)
Mark
but I've learnt not to worry about contingencies and just deal with matters
as they happen.
I would need a microscope to find your compassion, mate. That is one of the
defining characteristics of the 'Phil-o-phile'.
He has the hart of a Pussy.
"Bob Parker" <bobp.de...@bluebottle.com> wrote in message
news:460abdec$0$7405$5a62...@per-qv1-newsreader-01.iinet.net.au...
Trevor Wilson
>I realise that my breath is wholly wasted on this Philistine, but:
>
> A regulated circuit can benefit from the pre-regulation of the incoming
> AC.
**ANY pre-regulation should always be done at DC. AC regulation is
expensive, insane and unnecessary. With modern regulators, pre-regulation is
not likely to be required.
>
> Specifically, where the incoming AC strays outside the operating range of
> the regulating IC's output voltage, the benefits may include, for example,
> not having any blue smoke emanating from the unit.
**Again. Proper selection of transformer will eliminate any problems.
>
> Regulating IC's aren't expensive, so it seems a common sense precaution
> to make, particularly where other work, (the replacement of the existing
> wall-wart with a toroidal step down transformer) is envisaged. Which is
> EXACTLY what I originally indicated.
**No, it is not what you originally indicated.
--
Trevor Wilson
www.rageaudio.com.au
--
Posted via a free Usenet account from http://www.teranews.com
Trevor Wilson
"Mark" <marknospamp...@dodo.com.au> wrote in message
news:460a3c82$0$24870$c30e...@pit-reader.telstra.net...
>I realise that my breath is wholly wasted on this Philistine, but:
>
> A regulated circuit can benefit from the pre-regulation of the incoming
> AC.
>
> the regulating IC's output voltage, the benefits may include, for example,
> not having any blue smoke emanating from the unit.
>
> to make, particularly where other work, (the replacement of the existing
> wall-wart with a toroidal step down transformer) is envisaged. Which is
> EXACTLY what I originally indicated.
**BTW: Depending on your application (which you foolishly have declined to
tell us) a toroidal transformer may well be the WORST choice imaginable.
Toroidal transformers are certainly trendy and have a low radiated flux, but
they lose out to EI transformers in most other areas, including regulation
and line noise rejection. For the best line noise rejection, an 'R' core
transformer is best.
But you won't tell us what you are trying to do, so we really can't help
you.
Chris Jones
> The way I understand it, the regulation that already occurs within the
> application can only operate within a tolerance of the regulating IC's
> nominal input voltage. The application is using 15 Volt DC regulators
> (output), after the bridge rectifier, and can only operate (+/- x%) of 15
> volts DC input.
No. At the input of a typical 15V regulator you need 17V or 18V as a
minimum, and the maximum will typically be either around 30V-35V, or less
if large load currents are being drawn such that the heat sink of the
regulator gets so hot that the power dissipation of the regulator needs to
be reduced by lowering the input voltage below 30V.
>
> The rectification of (nominally) 9 VAC I understood to result in 18 VDC
No, not if the "(nominally) 9 VAC" is actually anywhere near 9VAC, the peak
value of the waveform is sqrt(2) (about 1.4 times) the RMS value, and 9VAC
is conventionally used to refer to 9VRMS, unless otherwise stated.
> (ignoring any small voltage drop across the diodes).
It is not small enough to ignore.
> So even when the
> input voltage is nominal,
> the input voltage to the regulating IC's is only within 20% of their
> nominal output.
It needs to be well ABOVE the nominal output OR IT WILL NOT WORK.
> Now what happens if the domestic supply voltage is not nominal?
If you are using the regulators properly, then they will regulate. On a bad
day, the output voltage might change by a millivolt or so, and nobody will
notice. On a good day it will change even less and you will have great
difficulty even measuring the change.
> If the domestic supply comes in at 264 VAC (+10%), the existing linear
> regulator now supplies 9.9 VAC to the application,
No, not if it is a regulator. Maybe you mean "transformer".
> the bridge rectifier
> doubles that to 19.8 VAC. The input voltage to the regulating IC's is now
> only within 40% of their nominal output!
Should work just fine with 19.8V into a 15V regulator.
> I monitor the domestic supply and regularly see voltages coming into our
> house outside the range of +/- 10%.
Ok, that's why you already have a regulator. If you are using it properly
then you should not be having any problems.
> One solution, of course, would be to redesign the power supply within the
> application's case, including upgrading the regulating IC's input voltage
> tolerance to at least 40% of its output, if such an IC can be found!
All common regulators will accept inputs 40% above the output voltage. It
is when the input voltage is NOT at least a couple of volts greater than
the output voltage that you will have trouble.
> However space within the applications case would not allow for a toroidal
> transformer, which I consider to be the optimum solution for a number of
> reasons that I don't need to explain here (or maybe they will insist that
> I do that as well?!!), and I have already invested considerable effort
> (and a small amount of money) in upgrading the capacitors within the
> existing application's power supply and really don't want to loose out on
> the already considerable improvements I have made therein.
I am not sure that you would make any improvement by changing the
capacitors. It is possible that you have introduced problems due to the
modifications. If you would explain what you have done then people would
probably help you, but you indicated that you did not want to do that.
> Quite frankly, I am astounded and reviled that such a simple request has
> generated such a vile reaction from this group. I can only assume that it
> is because they, like me, were unable to Goggle a suitable design. So as
> to maintain their allusion of expertise and so they hide their inability
> to self-design a suitable solution, with insults!
>
> I wonder what would happen if I took a simular request for such a simple
> thing to another newsgroup, say 'us.electronics', and pointed out to them
> that 'aus.electronics' does not have a single contributor who can satisfy
> the request. I wonder what they would say. "Too difficult", do you think?
The problem seems to be that you started out by asserting as facts a few
things that happen not to be correct, and then insulted anyone who tried to
point out your errors. If you had started out with more humility and less
conviction that you already knew everything on the subject of power
supplies, then you would have received more helpful replies.
I suggest you learn what is inside a voltage regulator and how it works
(from application notes on the National Semiconductor and On Semiconductor
websites if you don't have any suitable books), learn what a half-wave
rectifier and a full-wave bridge rectifier is, learn the relationship
between the peak and RMS voltages of a sine wave, and next time when you're
not sure about something, remember that you won't be attacked for not
knowing something but you will be mocked and insulted viciously if you
pretend to know things that you don't know and persist in asserting with
confidence things that are incorrect rather than listening to correct
(albeit not particularly polite) advice.
Chris
Poxy
> Well, I didn't think of searching for the '7815 datasheet', so fucking sue
> me.
That shows that you are not experienced in working with electronics -
anybody who regularly does searches for component numbers would
automatically add "datasheet". Furthermore, anyone with electronics
experience would understand the operating characteristics of a common linear
regulator without needing to refer to a datasheet - it's really common,
basic stuff.
> Either way, the cheapest solution is sounding like I should exchange the
> 7815 /7915 pair, for a pair that DOES have that 30V spec. and in so doing,
> eliminate the possible cause of the observed clipping during voltage
> overloads.
The first thing to do is measure voltages at key points - at the output of
the AC plugpack at the input of the regulators, at the output of the
regualtors etc. Boring I know, but that is how you start the diagnosis a
power supply problem. That you don't appear to realise that really basic
fact demonstrates a lack of knowledge and experience with simple power
supplies and suggests that you're not equipped to diagnose nor fix the
problem.
> Also, I take umbrage (offence, to you) at your trite analogy. It isn't an
> accurate portrayal of what happened or my actions or my motivations or my
> attitude. I would welcome a point-by-point comparison of your analogy and
my
> behaviour.
My analogy, horribly misspelt as it probably was, was reasonable, if not as
amusing as I would have liked. You clearly don't get how challenging it is
to design and implement what you wanted - it's *really* complex stuff. By
comparison, getting a standard dual-rail, linear regulator power supply to
behave is trivial.
The more I think about it, Bob's advice is correct - you should get someone
with a solid background in electronics to fix your preamp for you.
> Your PRESUMPTION that I must pay too much for my Black Gates is based on
> what? An ASSUMPTION that I pay foolish prices. That is both insulting AND
> ignorant (of how cheaply Black Gates can be purchased).
Hey, if they give the sparkling audio performance you like, fair enough. I
probably haven't paid enough attention to the musicality of the caps I buy.
> I also take umberage to your allegation that I am not "being straight-up
> with [this group]".
>
> You reckon that if i was being honest I would say "Actually, I built the
> engine, it's running badly, does anyone want to buy some really good fuel
> filters?" Here is why I wouldn't say such a thing:
>
> a) I didn't build the application, I modified it.
You never said that. It does explain a lot. In my analogy, it would be like
revealing that you'd modified your engine while at the same time giving the
strong impression you don't really know how engines work.
> b) It isn't running badly (under nominal conditions), it sounds superb.
> c) I am not SELLING anything.
That was a joke. Sorry. I was kind of thinking that if your "thing" didn't
end up working, you could recover some cash-money by Ebaying them fancy
caps.
> I look forward to our point-by-point comparison of your analogy with my
> behaviour. I can't find many comparisons at all. Do you do this often?
(that
> is: make up stupid analogies that just don't work).
Look, I've got nothing to add. I thought my insightful analogy would help
you understand why people responded to you with derision. Obviously you
still don't get it, and that seems to be because you don't have the
knowledge and experience in electronics to diagnose and solve the fault -
everything you say reinforces that fact.
Get someone who knows what they are doing to look at your device. If it's a
power supply problem they'll diagnose and fix it very quickly.
And you might be able to pay them in capacitors :)
Trevor Wilson
> BUT I DON'T want to eliminate the half wave rectifier!!! It is
> pre-existing inside the application.
>
> I don't want to alter the application, at all and I would prefer not even
> to discuss it.
>
> I would like to point out that my original question deliberately had
> NOTHING to do with the application. The easiest way to eliminate the
> unwanted discussion is to not provide information on the application.
>
> So, WE are stuck with AC as an input to the application. I wanted to
> eliminate the AC/AC wall-wart transformer (which uses an Iron core
> transformer) and replace if with a Toroidal core transformer.
>
> Do I need to justify this choice as well?
**YOU don't have to justify anything. YOU should be aware that, for low
level audio applications, a toroidal transformer will be your worst choice.
See what happens when you tell us what you are doing? You get sensible
answers. Dump the toroidal and look for a decent 'R' core transformer.
Additionally, I suggest you dump the 78XX & 79XX regulators and redesign
with LM317/LM337 regulators. Much more significant than bothering with those
silly Blackgate caps.
budgie
wrote:
>Black Gate Electrolytic Capacitors
>----------------------------------
>
>There are very few audio parts that promise a guaranteed improvement
>when replacing practically any other part, but this is what the BLACK
>GATE™ capacitors actually do. Exchanging any electrolytic capacitor
>anywhere in the circuit of a CD-player, amplifier or in the crossover of
>a speaker will greatly improve sound quality. BLACK GATE™ are recognised
>worldwide as the best electrolytics capacitors money can buy.
aaahhhh - the electrolytic equivalent of monster OFC cables ;-)
Trevor Wilson
"budgie" <m...@privacy.net> wrote in message
news:4c3m03ltbrbe507oe...@4ax.com...
> On Wed, 28 Mar 2007 23:02:47 +1000, Bob Parker
> <bobp.de...@bluebottle.com>
> wrote:
>
>
>>Black Gate Electrolytic Capacitors
>>----------------------------------
>>
>>There are very few audio parts that promise a guaranteed improvement
>>when replacing practically any other part, but this is what the BLACK
>>anywhere in the circuit of a CD-player, amplifier or in the crossover of
>>worldwide as the best electrolytics capacitors money can buy.
>
> aaahhhh - the electrolytic equivalent of monster OFC cables ;-)
**Not really. Monster Cables are designed to possess attractive cosmetics,
with no real regard for any tangible performance criteria. Blackgate caps,
OTOH, DO have some measurably significant parameters. HOWEVER, none of those
parameters is significant for power supply filtering. IOW: There are better
caps available, at lower cost for filtering. Mind you: After purchasing some
of those Dick Smith 'Joe Master' branded monstrosities once (and ONLY once)
I can readily understand why some purchasers would spend the Bucks for a cap
which is quite well made and performs respectably enough (Blackgate).
swanny
> The way I understand it, the regulation that already occurs within the
> application can only operate within a tolerance of the regulating IC's
> nominal input voltage. The application is using 15 Volt DC regulators
> (output), after the bridge rectifier, and can only operate (+/- x%) of 15
> volts DC input.
>
> the input voltage to the regulating IC's is only within 20% of their nominal
> output.
>
>
> only within 40% of their nominal output!
>
> house outside the range of +/- 10%.
>
> application's case, including upgrading the regulating IC's input voltage
> tolerance to at least 40% of its output, if such an IC can be found!
>
> transformer, which I consider to be the optimum solution for a number of
> reasons that I don't need to explain here (or maybe they will insist that I
> do that as well?!!), and I have already invested considerable effort (and a
> small amount of money) in upgrading the capacitors within the existing
> application's power supply and really don't want to loose out on the already
> considerable improvements I have made therein.
>
> generated such a vile reaction from this group. I can only assume that it is
> because they, like me, were unable to Goggle a suitable design. So as to
> maintain their allusion of expertise and so they hide their inability to
> self-design a suitable solution, with insults!
>
> I wonder what would happen if I took a simular request for such a simple
> thing to another newsgroup, say 'us.electronics', and pointed out to them
> that 'aus.electronics' does not have a single contributor who can satisfy
> the request. I wonder what they would say. "Too difficult", do you think?
>
Why do you need to regulate the input voltage to the regulator?
It is the function of the regulator to accept an unregulated input and provide a
stable, regulated output.
Mark
transformer AC power supply design."
So I actually didn't indicate what 'it' was that was being replaced. Good on
you for making that observation.
Brevity and relevance play a part in the formulation of my subjects for
obvious reasons. Limited character space being one of them.
I did indicate what I wanted to replace 'it' with, in the subject matter of
the OP.
So OK, why don't you help me select the 'self regulating' transformer that
will eliminate all my over voltage problems. 240 VAC in (nominal), 9 VAC
out. Fused at about 2 amps at the input. (it isn't critical.)
Tell me what else you need to know and I'll decide what I tell you, or not.
Regarding your speculation that "with modern regulators, pre-regulation is
not likely to be required.":
"Not Likely" is a very soft qualification in the face of the observed
behaviour of the applications performance during times of over supply. A
100% correlation suggests that it is VERY LIKELY. Statistically significant,
in other words.
What isn't clear is why my Regs (assuming it is my Regs) misbehave. I have
already conceded that the most cost effective action for me to take would be
to replace the 7815/7915 pair with a new pair that DOES have the 30V spec.
and see what happens.
But I may have to replace all other Regs in the applications power supply,
for the same reason, before I get to the bottom of it. I don't have the
necessary test equipment or the expertise to pre-determine which Regs are at
fault.
Apparently AC regulation is a difficult task. TXU certainly do it VERY
BADLY.
"Trevor Wilson" <tre...@SPAMBLOCKrageaudio.com.au> wrote in message
news:460acee8$0$16283$8826...@free.teranews.com...
Trevor Wilson
> The subject of the OP was "Isolated, regulated, toroidal step down
> transformer AC power supply design."
>
> So I actually didn't indicate what 'it' was that was being replaced. Good
> on you for making that observation.
>
> Brevity and relevance play a part in the formulation of my subjects for
> obvious reasons. Limited character space being one of them.
>
> I did indicate what I wanted to replace 'it' with, in the subject matter
> of the OP.
>
> So OK, why don't you help me select the 'self regulating' transformer that
> will eliminate all my over voltage problems. 240 VAC in (nominal), 9 VAC
> out. Fused at about 2 amps at the input. (it isn't critical.)
**Obtain a signal generator, capable of delivering a stable 50Hz sine wave.
Operate it into a small (say) 50 Watt power amp. Drive the power amp into a
suitable power transformer. That'll work.
>
> Tell me what else you need to know and I'll decide what I tell you, or
> not.
>
> Regarding your speculation that "with modern regulators, pre-regulation is
> not likely to be required.":
>
> "Not Likely" is a very soft qualification in the face of the observed
> behaviour of the applications performance during times of over supply. A
> 100% correlation suggests that it is VERY LIKELY. Statistically
> significant, in other words.
**Bullshit. The only time pre-regulation will be required, is for
under-Voltage events. That is easy enough to deal with.
>
> What isn't clear is why my Regs (assuming it is my Regs) misbehave.
**How (precisely) do they "misbehave"?
I have
> already conceded that the most cost effective action for me to take would
> be to replace the 7815/7915 pair with a new pair that DOES have the 30V
> spec. and see what happens.
**HUH? ALL 78XX/79XX regulators are specc'd virtually identically. Except
for a couple of low power variants, all have a 35 Volt maximum Vin limit.
Allhave a 2-2.5 Volt 'drop-out' Voltage. IOW: You should have AT LEAST 18
Volts DC at the regulator input terminal. There is a gotcha here too. You
need to measure the ripple too, as any ripple which has peaks falling below
the 2 - 2.5 Volt limit will impress that ripple on the output. IOW: Measure
the ripple to the input of the regulators.
>
> But I may have to replace all other Regs in the applications power supply,
> for the same reason, before I get to the bottom of it. I don't have the
> necessary test equipment or the expertise to pre-determine which Regs are
> at fault.
**Then you are screwed. You need to perform measurements to determine where
the problem is. I'll betcha it ain't the regulators. Regulators are VERY
reliable. And they all perform pretty much the same, if the have the same
designation.
>
> Apparently AC regulation is a difficult task.
**And a stupid idea.
TXU certainly do it VERY
> BADLY.
**TXU?
We're all bored with your top-posting now.