Orange Rocker 30, combo, 2006
N_Cook
Incidentally are the solder pads gold plated before soldering ?
No mention of PbF but appearance & paper & indent test hints at PbF. Crimps
adequte, switch functions ok, all solder points look good (for PbF) x5
inspection /tugging, preamp valve bases pass needle test. Other than
resolder most likely suspects , any known problem with these amps?
Phil Allison
"Nutcase Kook"
** The control pots on the front are absolute junk - one bump to any knob
and the pot back comes loose and easily result in intermittent sound.
.... Phil
N_Cook
I realised I was using the wrong gauge of cut down sewing needle and 2 of
the preamp valve socket pins are highly suspect. Those glossy white ceramic
mounts with holes just bigger than the valve pins.
Arfa Daily
"N_Cook" <div...@tcp.co.uk> wrote in message
news:i0abre$2i3$1...@news.eternal-september.org...
If it continues to cut out, a generator, a 'scope and a meter should tell
all. Valve circuits are very simple and very straightforward to trace
signals in, and troubleshoot. Even if it is a bad PbF joint, it should be
easy enough to pin it down to at least a stage, and possibly to a specific
component, based on valve voltages.
Arfa
Phil Allison
"Arfa Daily"
>
> If it continues to cut out, a generator, a 'scope and a meter should tell
> all. Valve circuits are very simple and very straightforward to trace
> signals in, and troubleshoot.
** You don't service that many valve guitar amps - do you ??
The ones that were originally well made are now so old they have strange
faults most techs have never seen before - while the ones made more
recently have designed in faults never seen before by anyone.
A few examples.
1. Recent Marshall combo amps with fibreglass PCBs that become LEAKY when
hot - output valve bias goes crazy and even the phase splitter stage goes
way out of DC balance in normal operation because of leakage from anode
tracks to grid tracks. There is simply no fix for this problem.
2. Recent Gibson /Trace Elliot amps that develop mysterious crackling
noises all over the circuit due to the use of water soluble flux that was
never properly washed of the PCB. Removing the main PCB entirely and
washing it thoroughly in solvent is the only fix.
3. Same amps as above use 9 pin PCB mount sockets that SHRINK - yep,
the plastic material used to make the socket shrinks under the heat from
EL84s, reducing the pitch circle diameter so much it is impossible to fit a
new tube in the socket. Replacing all the output valve sockets is the only
fix.
Then there are all the issues with the valves themselves - all new
production now comes from China or the former USSR and most of the valves
have designed in faults of kinds that were never seen previously. Eg.
nearly all 12AX7s now crackle and pop if tapped with the back of a
screwdriver and/or have bad heater cathode hum or are very microphonic -
while octal power types often suffer from bad soldering (PbF ?) on the pins
causing all manner of weird intermittents when the solder joint lets go.
Yep - fixing valve amps is pure joy.
.... Phil
N_Cook
news:47bWn.34349$9c1.22170@hurricane...
Coincidence or action of high V on springiness of the socket metal?
One valve base, pin 1 , the other pin 6 , both anodes so killing throughput
if connection fails.
While on valve stuff , has anyone come across any output transformer or
mains transformer ,for that matter, in any equipment , where there is
failure of PbF joint inside the transformer where tail meets magnet wire?
Arfa Daily
"Phil Allison" <phi...@tpg.com.au> wrote in message
news:i0bgp3$f5c$1...@news-01.bur.connect.com.au...
>
> "Arfa Daily"
>>
>> If it continues to cut out, a generator, a 'scope and a meter should tell
>> all. Valve circuits are very simple and very straightforward to trace
>> signals in, and troubleshoot.
>
> ** You don't service that many valve guitar amps - do you ??
Er, that would be a yes then ... Probably three or four a week, most every
week, and have been doing them for around 40 years ... Whilst some faults
are a little obscure, most are very straightforward, and I'm sure that you
don't have any more trouble fixing them, than I do Phil. I would pick a
fault on a valve amp over a transistor one, every time, as would probably
any engineer who has ever worked with valves. Every stage is pretty much
independent, and troubleshoot-able as a separate entity. You can't say that
about most transistor amps.
>
> The ones that were originally well made are now so old they have strange
> faults most techs have never seen before - while the ones made more
> recently have designed in faults never seen before by anyone.
>
> A few examples.
>
> 1. Recent Marshall combo amps with fibreglass PCBs that become LEAKY
> when hot - output valve bias goes crazy and even the phase splitter
> stage goes way out of DC balance in normal operation because of leakage
> from anode tracks to grid tracks. There is simply no fix for this
> problem.
Care to give me a model for that behaviour ? I see a lot of Marshall combos,
as they are built just a few miles from where I live. I have not seen any
similar problems here. I used to visit Jim Marshall in his factory in the
early days. He was a very good friend of a friend of mine. As to the problem
with a - g leakage, I would have thought that you might have been able to
get away with isolating the affected tracks by cutting or even removing them
from the board completely, and then hard wiring.
>
> 2. Recent Gibson /Trace Elliot amps that develop mysterious crackling
> noises all over the circuit due to the use of water soluble flux that was
> never properly washed of the PCB. Removing the main PCB entirely and
> washing it thoroughly in solvent is the only fix.
>
> 3. Same amps as above use 9 pin PCB mount sockets that SHRINK - yep,
> the plastic material used to make the socket shrinks under the heat from
> EL84s, reducing the pitch circle diameter so much it is impossible to fit
> a new tube in the socket. Replacing all the output valve sockets is the
> only fix.
>
> Then there are all the issues with the valves themselves - all new
> production now comes from China or the former USSR and most of the valves
> have designed in faults of kinds that were never seen previously. Eg.
> nearly all 12AX7s now crackle and pop if tapped with the back of a
> screwdriver and/or have bad heater cathode hum or are very microphonic -
> while octal power types often suffer from bad soldering (PbF ?) on the
> pins causing all manner of weird intermittents when the solder joint lets
> go.
Whilst I would agree that valve quality is not as good as it was when the
likes of Mullard and Brimar etc made them, I also don't think that they are
quite as bad as you seem to find them, if you buy decent quality ones, or
manufacturer's originals, which have been vetted by the amp manufacturer as
being of the required quality. The Ruby HG (Hi Grade) 12AX7s that I use,
don't crackle and pop, and are no more microphonic than any high gain
triodes have ever been. I also don't find the h - k leakage bad either -
certainly not enough to identify as being a predominant source of unwanted
hum. And as to bad soldering on octal base pins, I honestly can't say that
I've ever seen this problem on any amp that's been across my bench, or on
any replacement valves that I have fitted, which may have had their bases
connected to the leadouts by PbF. Perhaps I've just been lucky ...
>
> Yep - fixing valve amps is pure joy.
>
>
> .... Phil
>
>
Well, I find it so ...
Arfa
Phil Allison
"Arfa Daily"
> "Phil Allison"
>>
>>> If it continues to cut out, a generator, a 'scope and a meter should
>>> tell all. Valve circuits are very simple and very straightforward to
>>> trace signals in, and troubleshoot.
>>
>> ** You don't service that many valve guitar amps - do you ??
>
>
> Er, that would be a yes then ... Probably three or four a week, most
> every week, and have been doing them for around 40 years ... Whilst some
> faults are a little obscure, most are very straightforward, and I'm sure
> that you don't have any more trouble fixing them, than I do Phil.
** I fix them all - of course.
But there is plenty of trouble with most of them.
> I would pick a fault on a valve amp over a transistor one, every time, as
> would probably any engineer who has ever worked with valves.
** Solid state gear is far easier to fix and make stay fixed - IM long E.
>> The ones that were originally well made are now so old they have strange
>> faults most techs have never seen before - while the ones made more
>> recently have designed in faults never seen before by anyone.
>>
>> A few examples.
>>
>> 1. Recent Marshall combo amps with fibreglass PCBs that become LEAKY
>> when hot - output valve bias goes crazy and even the phase splitter
>> stage goes way out of DC balance in normal operation because of leakage
>> from anode tracks to grid tracks. There is simply no fix for this
>> problem.
>
>
> Care to give me a model for that behaviour ?
** Yep - the JCM2000: TSL100 combo series.
Easy to find many stories about the same problem on usenet and web forums.
> I see a lot of Marshall combos, as they are built just a few miles from
> where I live. I have not seen any similar problems here. I used to visit
> Jim Marshall in his factory in the early days. He was a very good friend
> of a friend of mine.
** Nice guy - who never designed or built an amp in his life.
> As to the problem with a - g leakage, I would have thought that you might
> have been able to get away with isolating the affected tracks by cutting
> or even removing them from the board completely, and then hard wiring.
** Tried that idea with the very first example I ever came across.
The PCB wound up looking like a piece of Swiss cheese and still the problem
was not cured.
The only "treatment" that helped at all was to install a fan to keep the
valves and hence PCB cooler.
Colleagues have complained to me about the exact same problem.
> Whilst I would agree that valve quality is not as good as it was when the
> likes of Mullard and Brimar etc made them, I also don't think that they
> are quite as bad as you seem to find them, if you buy decent quality ones,
> or manufacturer's originals, which have been vetted by the amp
> manufacturer as being of the required quality.
** The BAD valves are already fitted in the amps that come to me for
service.
There are NO " manufacturers originals" available in Australia AFAIK.
> The Ruby HG (Hi Grade) 12AX7s that I use, don't crackle and pop, and are
> no more microphonic than any high gain triodes have ever been.
** Yaaawwwnnnnnn.....
You compare the particular with the general.
How tedious.
> I also don't find the h - k leakage bad either - certainly not enough to
> identify as being a predominant source of unwanted hum.
** How odd then that so many new generation valve amps use DC supply for
heaters JUST because of this issue.
> And as to bad soldering on octal base pins, I honestly can't say that I've
> ever seen this problem on any amp that's been across my bench,
** What planet do you live on ???
.... Phil
Arfa Daily
"Phil Allison" <phi...@tpg.com.au> wrote in message
news:i0cp5t$5t2$1...@news-01.bur.connect.com.au...
Apparently, a very different one from you ...
But then, of course, I was forgetting who I was trying to have a reasoned
discussion with. It had completely slipped my mind that anyone who looks at
anything from a different point of view to you, must be wrong. I suppose
you'll start in on the hysterical abuse hurling next. Well, if that's what
you need to do, go right ahead. I really don't care. And I suppose you know
Jim all the way from upside down land do you ?
Arfa
>
Geoffrey S. Mendelson
> Er, that would be a yes then ... Probably three or four a week, most every
> week, and have been doing them for around 40 years
If you are such an expert, please tell us how they got that volume
control to go to 11, while (whilst?) everyone knows they only go to 10?
:-)
Geoff.
--
Geoffrey S. Mendelson, Jerusalem, Israel g...@mendelson.com N3OWJ/4X1GM
I do multitasking. If that bothers you, file a complaint and I will start
ignoring it immediately.
Arfa Daily
"Geoffrey S. Mendelson" <g...@cable.mendelson.com> wrote in message
news:slrni2kht...@cable.mendelson.com...
If I told you that Geoff, I'd be destroying my niche market. Suffice to say
that they used triodes with more than three electrodes ... d;~}
Arfa
Phil Allison
"Arfa Daily"
>
>> ** What planet do you live on ???
>>
>
** Where reality never intrudes on you rose tinted view.
> But then, of course, I was forgetting who I was trying to have a reasoned
> discussion with.
** Shame you have not seen or MISSED the common valve amp faults I
mentioned.
Maybe Marshall, Gibson, Fender, Peavey and others ship their bad batches to
Australia deliberately or maybe you have been leading a charmed existence.
> It had completely slipped my mind that anyone who looks at anything from a
> different point of view to you, must be wrong.
** Now you are completely off with the fairies.
What you have NOT see cannot be dismissed as non existent.
> I suppose you'll start in on the hysterical abuse hurling next.
** You are supplying plenty of smug, pommy provocations for that.
> Well, if that's what you need to do, go right ahead. I really don't care.
** You don't have a case or a clue - really.
> And I suppose you know Jim all the way from upside down land do you ?
** Jim Marshall visited Australia a number of years back, did interviews
with the trade press and gave a presentation to an audience of industry folk
in Sydney.
Before Jim accepted any questions, the MC gave a stern warning to the
assembled audience that Jim was not involved in the design or manufacture of
Marshall amps and that no questions about the notoriously poor design or
appalling reliability of the amps would be allowed.
Wise move.
.... Phil
Dave Platt
Arfa Daily <arfa....@ntlworld.com> wrote:
>> If you are such an expert, please tell us how they got that volume
>> control to go to 11, while (whilst?) everyone knows they only go to 10?
>>
>> :-)
>If I told you that Geoff, I'd be destroying my niche market. Suffice to say
>that they used triodes with more than three electrodes ... d;~}
Let me guess... instead of using thorium as a dopant in the filaments
to enhance electron emission, they used quadmium, right?
--
Dave Platt <dpl...@radagast.org> AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!
Geoffrey S. Mendelson
> If I told you that Geoff, I'd be destroying my niche market. Suffice to say
> that they used triodes with more than three electrodes ... d;~}
I figure you could get an extra 20 to 30 quid an amp if you offered to
upgrade them from a maximum of 10 to 11. :-)
Arfa Daily
"Dave Platt" <dpl...@radagast.org> wrote in message
news:tviqf7-...@radagast.org...
> In article <VqwWn.84179$_F1.18386@hurricane>,
> Arfa Daily <arfa....@ntlworld.com> wrote:
>
>>> If you are such an expert, please tell us how they got that volume
>>> control to go to 11, while (whilst?) everyone knows they only go to 10?
>>>
>>> :-)
>
>>If I told you that Geoff, I'd be destroying my niche market. Suffice to
>>say
>>that they used triodes with more than three electrodes ... d;~}
>
> Let me guess... instead of using thorium as a dopant in the filaments
> to enhance electron emission, they used quadmium, right?
>
> --
> Dave Platt <dpl...@radagast.org> AE6EO
How did you know that, huh ? Well that's just great. Now you've told
everyone, and my plans to dominate the music world with one notch upgrades,
are in shreds. Cheers pal ...
Arfa :-)
Geoffrey S. Mendelson
> If I told you that Geoff, I'd be destroying my niche market. Suffice to say
> that they used triodes with more than three electrodes ... d;~}
Don't forget to sell them these:
http://global.aopen.com/products_detail.aspx?Auno=53
Although they have long since been discontinued (or deleted in English).
Arfa Daily
"Geoffrey S. Mendelson" <g...@cable.mendelson.com> wrote in message
news:slrni2maf...@cable.mendelson.com...
> Arfa Daily wrote:
>
>> If I told you that Geoff, I'd be destroying my niche market. Suffice to
>> say
>> that they used triodes with more than three electrodes ... d;~}
>
> Don't forget to sell them these:
>
> http://global.aopen.com/products_detail.aspx?Auno=53
>
> Although they have long since been discontinued (or deleted in English).
>
> Geoff.
>
> --
Oh, that's soooo unfair. I was just about to put in an order for some of
those to use as the controller for my LED pilot bulb replacement upgrade ...
Rats. I guess it's back to using the warehouse full of ZX Spectrums that
I've got then ... :-|
Arfa
N_Cook
What is the state of the vacuum-formed plastic of the Sinclair ZX80s these
days?
Arfa Daily
"N_Cook" <div...@tcp.co.uk> wrote in message
news:i0fr3p$a8g$1...@news.eternal-september.org...
I'd forgotten that ! Dunno. haven't seen one in years ...
Arfa
Gareth Magennis
>>> The ones that were originally well made are now so old they have strange
>>> faults most techs have never seen before - while the ones made more
>>> recently have designed in faults never seen before by anyone.
>>>
>>> A few examples.
>>>
>>> 1. Recent Marshall combo amps with fibreglass PCBs that become LEAKY
>>> when hot - output valve bias goes crazy and even the phase splitter
>>> stage goes way out of DC balance in normal operation because of leakage
>>> from anode tracks to grid tracks. There is simply no fix for this
>>> problem.
>>
>>
>> Care to give me a model for that behaviour ?
>
>
> ** Yep - the JCM2000: TSL100 combo series.
>
> Easy to find many stories about the same problem on usenet and web forums.
>
>
Yes, Marshal TSL 100. Sigh. I have had two of these with faulty
PCB's. They do indeed leak, and destroy the output tubes, as the bias
goes totally crazy.
I spent hours on the first one trying to establish what the fuck was going
on, as it made no sense whatsoever.
Eventually I phoned Marshall. They know about this problem and are unable
to fix it. You need to replace the PCB with an upgraded design.
Gareth.
Phil Allison
"Gareth Magennis"
** Hope the are willing to supply that for free ??
Whole PCBs going leaky is hardly an example of "normal wear and tear".
.... Phil
Gareth Magennis
Er, no they ae not.
Gareth.
Jeffrey D Angus
>
>
Tube sockets and PCBs have always been a problem.
The trick is to bite the bullet and mount the high power
tubes on the metal chassis and hand wire them to the
rest of the low power stuff on the PCB.
Jeff
--
“Egotism is the anesthetic that dulls the pain of stupidity.”
Frank Leahy, Head coach, Notre Dame 1941-1954
N_Cook
news:aeOYn.160095$NW.122981@hurricane...
Is there any surface appearance hint? slight crazing/discolouration? would a
1000V / 1Gohm insulation tester show anything and is the conductive path in
the bulk or the surface? I've seen this problem with sockets going
conductive but that is due to arcing/localised heating and charring so
somewhat obvious