ESR Meters

[Jerry G.]

You need an ESR meter because you want to know the reactive
resistance (impedance) of the capacitor. The ESR meters used for
troubleshooting were designed to meet specific requirement to easily
find bad caps.

If you try different approaches you may never be too sure if you have
the optimum method to achieve what you want. You would be best to do
proper research into the application if you are devising your own
method that is not an industry standard...

--

Jerry Greenberg

===========================================
Email: jerr...@hotmail.com
Home Page: http://www.zoom-one.com
Components: http://www.zoom-one.com/electron.htm
Products: http://shop.affinia.com/jerryg50/Store1/
Navigation: http://www.zoom-one.com/navigati.htm
Sci/Inst: http://www.zoom-one.com/actel.htm
Personal: http://www.total.net/~jerryg

Electronic Components, And Navigation Compasses

============ Message Separator ===============

"Tom Del Rosso" <NoSpam.Pleas...@att.net> wrote in message
news:hcwF4.4813$pK3.4...@bgtnsc04-news.ops.worldnet.att.net...
Can you use a curve tracer as an ESR meter? If yes, what do you look
for in
the trace?

[Tom Del Rosso]

[Stephen M. Powell]

>Can you use a curve tracer as an ESR meter? If yes, what do you look for in
>the trace?

Unlikely, but it's easy enough to build an oscilloscope adapter to do
the job.

See:
Electronic Hobby Information
- Stuff that should be easy to find, but isn't
"99 Cent ESR Test Adapter"
http://www.freeyellow.com/members5/octopus/

Actually,sometimes you can see sort of a curve trace as the
capacitor charges up under test conditions

To reply by e-mail, remove the obvious 8 character political
statement: smpo...@taxspam.usa.net

[Martin Pickering {UK}]

In article <hcwF4.4813$pK3.4...@bgtnsc04-news.ops.worldnet.att.net>,

"Tom Del Rosso" <NoSpam.Pleas...@att.net> wrote:

>Can you use a curve tracer as an ESR meter? If yes, what do you look for in
>the trace?

The whole point of an ESR meter was to provide a means of carrying out
quick, simple in-circuit test.

You could use a 'scope but you'd have to provide a sine wave source at
about 100kHz, 100mV I believe. Seems awkward and Bob Parker's ESR meter
isn't very expensive. See:

http://www.netcentral.co.uk/satcure/design/genie.htm

Martin

[JURB6006]

Put the thing in the diode mode, stick a diode on it, and parelell to the DUT.
Of course you will have to learn to read it.

There are other ways, I simply use a square wave generator and a scope. Works
great, once you know how to read it.

[John Bachman]

Martin Pickering {UK} wrote in message ...

Or in the US: http://www.anatekcorp.com

[Tom Del Rosso]

"Jerry G." <jerr...@hotmail.com> wrote in message
news:DHyF4.208$vg7....@news.total.net...

> You need an ESR meter because you want to know the reactive
> resistance (impedance) of the capacitor. The ESR meters used for
> troubleshooting were designed to meet specific requirement to easily
> find bad caps.

I gather that an ESR meter produces current pulses and measures voltage, and a
curve tracer produces a voltage waveform and measures current. I suppose
that's why they're not interchangeable?

Thanks to all respondents.

[KenO]

Hi,

Am new to ESR Meters so have been searching the Internet and Forums for info.

Appreciate comments from others that have been using ESR Meters as to what features would be included in an "Ideal ESR Meter"

Thanks

Ken

[John Robertson]

The Bob Parker (Blue) ESR meter kit has most of the best features
(pretty much the gold standard meter), the only recommendation I have
with it is to also check across the capacitor with an ohm-meter to make
sure the low reading is because the capacitor is shorted...

Oh, and I happen to sell those, have been since 1999! We use one in the
shop all the time.

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

[Jeff Liebermann]

On Fri, 10 Jul 2015 07:42:06 -0700 (PDT), KenO <kenit...@yahoo.com>
wrote:

>Am new to ESR Meters so have been searching the Internet and Forums for info.
>Appreciate comments from others that have been using ESR Meters as to
>what features would be included in an "Ideal ESR Meter"

I have 3 ESR meters.
1. The original Dick Smith red LED meter.
<https://www.flippers.com/esrktmtr.html>
2. Capacitor Wizard analog meter:
<http://midwestdevices.com>
3. A Chinese components tester:
<http://www.ebay.com/itm/281538476673>

All work quite well. I mostly use the Capacitor Wizard because the
meter reading is faster than the digital variety, that requires
shorting the leads to zero the display (to remove test cable
resistance from the measurement). However, this meter is not terribly
accurate below about 1 ohm. Good enough for testing electrolytic
capacitors, but not good for measuring battery ESR.

I'm not going to rattle off a bullet list of features for my idea of
an ideal ESR meter. They are unlikely to apply to your unstated
purpose. Instead, you might try to describe what you're doing and how
an ESR meter would fit into your application. That will define the
required features. We can then recommend a suitable product or design
(if you want to build your own).

--
Jeff Liebermann je...@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

[Trevor Wilson]

**Up until last year, I was using the Bob Parker ESR meter. Excellent
device. Foolproof, cheap and very handy. OTOH, I bought one of these
last year:

http://www.peakelec.co.uk/acatalog/jz_esr70.html

Very, VERY nice instrument. I use it every day. If you budget can
stretch, it is highly recommended.



--
Trevor Wilson
www.rageaudio.com.au

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[Ralph Mowery]

"Trevor Wilson" <tre...@SPAMBLOCKrageaudio.com.au> wrote in message
news:d0bahr...@mid.individual.net...

>> **Up until last year, I was using the Bob Parker ESR meter. Excellent
> device. Foolproof, cheap and very handy. OTOH, I bought one of these last
> year:
>
> http://www.peakelec.co.uk/acatalog/jz_esr70.html
>
> Very, VERY nice instrument. I use it every day. If you budget can stretch,
> it is highly recommended.
>
>
>

If that is too much, you can get about the same thing without a caes from
China for $ 16 including shipping.
There are several on ebay similar to this one. They check almost any small
signal component.

Ebay number

271611840945

[Phil Allison]

Jeff Liebermann wrote:


>
> All work quite well. I mostly use the Capacitor Wizard because the
> meter reading is faster than the digital variety, that requires
> shorting the leads to zero the display (to remove test cable
> resistance from the measurement).

** How absurdly lazy, zeroing only takes one or two seconds and does not need to be repeated unless the meter is switched off. All ESR readings are virtually instantaneous after that.

If the cap is being tested out of circuit, no leads are normally needed.

> However, this meter is not terribly accurate below about 1 ohm.
> Good enough for testing electrolytic capacitors,

** No it isn't.

The ESR of most electros of over 1000uF is under 0.05 ohms.



... Phil

[Lee]

On 11/07/2015 02:38, Trevor Wilson wrote:
> On 11/07/2015 12:42 AM, KenO wrote:
>> Hi,
>>
>> Am new to ESR Meters so have been searching the Internet and Forums
>> for info.
>>
>> Appreciate comments from others that have been using ESR Meters as to
>> what features would be included in an "Ideal ESR Meter"
>>
>
> **Up until last year, I was using the Bob Parker ESR meter. Excellent
> device. Foolproof, cheap and very handy. OTOH, I bought one of these
> last year:
>
> http://www.peakelec.co.uk/acatalog/jz_esr70.html
>
> Very, VERY nice instrument. I use it every day. If you budget can
> stretch, it is highly recommended.
>
>

+1 have one of those as well.
To the other poster, I also have a couple of different Chinese clones,
yes they work, (fsvow at least), but the Peak is simply much nicer to use.

[Phil Allison]

> "Ideal ESR Meter".


** For a start, all the ones that Bob Parker included in his design.

Being able to test the capacitance value would be an advantage, but doing so reliably when the part is still in circuit is near impossible.

Be aware that the ESR meters intended for service work are only good for electrolytic caps ( regular aluminium and tantalum ) and interpreting the readings correctly requires significant operator knowledge and/or a similar electro to compare with.



... Phil

[N_Cook]

The cheapo fleabay one, I could not find the pk-pk voltage in ESR mode,
in the specs. Do you know what it is? I consider that to be a vital
requirement as most of my testing is in-circuit , unlike the shown
examples of isoltated componenent testing. Must be no more than .2V and
ideally .1V, so as not to turn on anything active, in circuit

[Cursitor Doom]

On Sat, 11 Jul 2015 02:52:21 -0700, Phil Allison wrote:

> Be aware that the ESR meters intended for service work are only good for
> electrolytic caps ( regular aluminium and tantalum ) and interpreting
> the readings correctly requires significant operator knowledge and/or a
> similar electro to compare with.

...Or a table of expected values vs. voltage rating vs. capacitance -
which comes with the Peak meter.

[Michael Black]

Surely if one buys an ESR meter, they should be practicing with it. Check
every electrolytic and tantalum, get a feel for the variation. Don't just
use the meter to "check some electrolytics that look bad" and be done with
it, until the next time you need to use the meter.

Michael

[Phil Allison]

** IME, such tables are far too vague and of date for modern electros.

The goal in servicing & refurbishing work is to find electro caps that are *on the way out* as well as obviously dead ones.

If in doubt, comparison with a the closest new electro available is a good move.


... Phil

[Cursitor Doom]

Well maybe. But it'll slow the process down massively as it's not just
the capacitance that causes ESR values to change. As you well know.

[Jeff Liebermann]

On Fri, 10 Jul 2015 22:17:55 -0700 (PDT), Phil Allison
<palli...@gmail.com> wrote:

>Jeff Liebermann wrote:
>> All work quite well. I mostly use the Capacitor Wizard because the
>> meter reading is faster than the digital variety, that requires
>> shorting the leads to zero the display (to remove test cable
>> resistance from the measurement).

>** How absurdly lazy, zeroing only takes one or two seconds
>and does not need to be repeated unless the meter is switched off.
>All ESR readings are virtually instantaneous after that.

The banana or pin jacks found on some ESR meters, including my Dick
Smith K-7204, do not make a reliable connection. The associated
probes are not much better. If I move the leads, I'll see some
variations in reading from the change in lead resistance. However,
you're correct about me being lazy. I should have soldered the jacks
and the probes long ago. (Added to things to do list for today).

>If the cap is being tested out of circuit, no leads are normally needed.

I do test caps out of the circuit, but only after I've unsoldered them
from the PCB. That's to verify that they really were bad. Other than
that, I rarely measure individual components, except when the markings
have disappeared. 2 of my 3 ESR meters have soldered leads. It will
shortly be 3 of 3 making measurements without test leads impossible.

>> However, this meter is not terribly accurate below about 1 ohm.
>> Good enough for testing electrolytic capacitors,
>
>** No it isn't.
>
>The ESR of most electros of over 1000uF is under 0.05 ohms.

It can become a problem with the Cap Wizard at 100 uF.
See the manual at:
<http://midwestdevices.com/_pdfs/Capmanual9.pdf>
See the table of "Capacitor Types and Expected ESR - 1uf & up"
For 1 uF and up, they consider anything less than 3 ohms as good.
However, you're correct. When I measure a BFC (big fat capacitor),
usually in a power supply, a digital meter is needed. I use this
chart for reference:
<http://802.11junk.com/jeffl/crud/ESR.txt>

There's also some interesting stuff in the Cap Wizard manual on
measurements with parallel inductance and resistance.

[Ralph Mowery]

"N_Cook" <div...@tcp.co.uk> wrote in message
news:mnqp40$9qv$1...@dont-email.me...

>
> The cheapo fleabay one, I could not find the pk-pk voltage in ESR mode, in
> the specs. Do you know what it is? I consider that to be a vital
> requirement as most of my testing is in-circuit , unlike the shown
> examples of isoltated componenent testing. Must be no more than .2V and
> ideally .1V, so as not to turn on anything active, in circuit

The fleabay one uses the same basic circuit design as the Peak meter. Peak
is screwing the people as they make one for non simiconductor devices and
another one for simiconductors. Whe ebay one does both and the origional
software for them does both using the same circuits.

I don't know the specs for it, but I did put it on a analog scope and from
what I can tell when I hook a capacitor across it there is a large voltag
pulse around 4 votls or so and then a low voltage pulse of about .2 volts.
Both going +and -.

[Phil Allison]

Cursitor Doom wrote:

> >>
> >> > Be aware that the ESR meters intended for service work are only good
> >> > for electrolytic caps ( regular aluminium and tantalum ) and
> >> > interpreting the readings correctly requires significant operator
> >> > knowledge and/or a similar electro to compare with.
> >>
> >> ...Or a table of expected values vs. voltage rating vs. capacitance -
> >> which comes with the Peak meter.
> >
> >

> > ** IME, such tables are far too vague and out of date for modern electros.

> >
> > The goal in servicing & refurbishing work is to find electro caps that
> > are *on the way out* as well as obviously dead ones.
> >
> > If in doubt, comparison with a the closest new electro available is a
> > good move.
>
> Well maybe. But it'll slow the process down massively as it's not just
> the capacitance that causes ESR values to change. As you well know.

** See page 9 of the Peak ESR meter user's guide.

http://www.peakelec.co.uk/resources/esr60_userguide_en.pdf

The ESR values shown in the table up to 470uF are several times higher than normally found with new caps of the same ratings.

When servicing, the task is to identify electros whose ESR has risen significantly, indicating end of useful life. Cos most of the electrolyte that was there when new has escaped and evaporated.



.... Phil

[N_Cook]

Thanks for that, I suppose at that price its worth getting as a
spare/second opinioner. My old one is 15KHz sine , or was before
clamping with reversed germanium diodes across the probes, to limit the
applied voltage, but it is good enough for go/no-go of >5uF or so electros.

[Cursitor Doom]

On Sat, 11 Jul 2015 22:06:30 -0700, Phil Allison wrote:

> Cursitor Doom wrote:
>
>
>> >> > Be aware that the ESR meters intended for service work are only
>> >> > good for electrolytic caps ( regular aluminium and tantalum ) and
>> >> > interpreting the readings correctly requires significant operator
>> >> > knowledge and/or a similar electro to compare with.
>> >>
>> >> ...Or a table of expected values vs. voltage rating vs. capacitance
>> >> -
>> >> which comes with the Peak meter.
>> >
>> >
>> > ** IME, such tables are far too vague and out of date for modern
>> > electros.
>> >
>> > The goal in servicing & refurbishing work is to find electro caps
>> > that are *on the way out* as well as obviously dead ones.
>> >
>> > If in doubt, comparison with a the closest new electro available is a
>> > good move.
>>
>> Well maybe. But it'll slow the process down massively as it's not just
>> the capacitance that causes ESR values to change. As you well know.
>
>
> ** See page 9 of the Peak ESR meter user's guide.
>
> http://www.peakelec.co.uk/resources/esr60_userguide_en.pdf

This bit makes no sense to me:

"To allow the self-protection mechanism to function, always ensure that
the Atlas ESR has completed any analysis before connecting the test
probes to a component." :-/

[Mark Justice]

www.aliexpress.com
search term: Mega328
$9.99

On your recommendation I'm ordering one.
Allow 3 - 4 weeks delivery.
I've ordered about 30 times from them and all good so far.

[M Philbrook]

In article <mntii7$noo$3...@dont-email.me>, cu...@notformail.com says...

Why? At least it's providing some sort of internal protection.

Just wait for it to fully boot or put some unknown charged cap on
the leads before switching it on. At least you can help them
to stay in business.

Jamie

[jurb...@gmail.com]

>> "To allow the self-protection mechanism to function, always ensure that
>> the Atlas ESR has completed any analysis before connecting the test
>> probes to a component." :-/
>
> Why? At least it's providing some sort of internal protection.
>
> Just wait for it to fully boot or put some unknown charged cap on
>the leads before switching it on. At least you can help them
>to stay in business.
>
>Jamie "

To say the least, this is not enticing me to buy one. One kilohertzz square wave at 400 mV amplitude positive going, with a scope freewheeled into sync and DC coupled. The most effective lytic checker in the world once you lern to read it.

Once you learn to read it. I invented it, I used it to great profit and productivitly and I taught others how to use it, but only where I worked.

Now that I am older and ready to die Imight be tempted to reveal all the details. the bottom line is that tis thing read directly RIGHT NOW, no waiting for some stupid program to run. Like the one they had at opjne job, the son of a bitch sat there and said "DISCHARGING". The fuck you cre if it is charged ? Just read the AC resistance.

Well my scope doodad does exactly that and if the cap is charged then the scope will still read correctly on AC and not iondicate the cap is charged. BTW, does it occur to anyone that IF the cap is charged that it holds a charge and therefore is probably good ? Or are you testing for 0.05 ohms of ESP in the filter caps of an audio amp and giving name to the term "audiophool" ?

It is amazing they do not teach this. you put a signal to a device - the DUT - and then measure what is does. What is not simple about that ? God damn, I figured out this cap checker witht eh scope thing when I was about 16. ON MY OWN. Fuck Dick Smith. Well not really but you know what I mean. In fact I made a trade with Bob Parker. Some knobs for a Ysamaha receiver for an elcheapo boomerang. Hey, it came back a few times which proved it was not just a stick, but then the kids got ahold of it and it was then a stick. Know what I mean ?

[Ralph Mowery]

"Michael Black" <et...@ncf.ca> wrote in message
news:alpine.LNX.2.02.1...@darkstar.example.org...

>> Surely if one buys an ESR meter, they should be practicing with it.
>> Check
> every electrolytic and tantalum, get a feel for the variation. Don't just
> use the meter to "check some electrolytics that look bad" and be done with
> it, until the next time you need to use the meter.
>

That should be done with any piece of equipment. Practice with it and learn
the odd things about them.

That $ 15 component tester will sometimes show odd results of the older
transistors and if you change the leads around it will show up differant.
This is also in some of the documentation of the tester.

Where I worked there were many wires in a conduit carring 120 volt control
voltage. With a digital meter there was so much induced voltage you could
not tell if a wire was really active or not. You had to put some kind of a
load on them. YOu could take an analog meter and start with a high voltage
range and then switch to a lower range. If the meter stayed in the same or
near the same physical position, it was just showing the induced voltage.
Even with a wire disconnected at each end,it would still shock the crap out
of you due to that voltage.

[Phil Allison]

Ralph Mowery wrote:

>
> That should be done with any piece of equipment. Practice with it and learn
> the odd things about them.

** As Clint Eastwood might have said: " a man's gootta know the limitations of his test gear ... "

> Where I worked there were many wires in a conduit carring 120 volt control
> voltage. With a digital meter there was so much induced voltage you could
> not tell if a wire was really active or not. You had to put some kind of a
> load on them. YOu could take an analog meter and start with a high voltage
> range and then switch to a lower range. If the meter stayed in the same or
> near the same physical position, it was just showing the induced voltage.
> Even with a wire disconnected at each end,it would still shock the crap out
> of you due to that voltage.

** Electricians once regularly used 40W bulbs in a protected, hand held fittings to test if circuits were live - see pic.

https://img1.etsystatic.com/068/0/6320982/il_fullxfull.780718127_nbxf.jpg

The AC plug was replaced with two probes in the examples I saw.

I guess it was important to test the bulb before each use ...


... Phil

[Rheilly Phoull]

"Phil Allison" wrote in message
news:c22de235-2de2-4439...@googlegroups.com...

Sure was, then there was the 2 15w pilot lamp bulbs wired in series for the
3 phase stuff (Hi - tech)!!
Along came the "Wiggy" which was more robust,
http://www.ebay.com/bhp/wiggy-voltage-tester
The important part was that the tester was putting a load on the circuit
where neon testers and digital
testers don't.

[John G]

Phil Allison has brought this to us :

Some used 2 bulbs in paper bakelite tubes wired in series then they
could test line to line or line to neutral with the same device without
worrying about the voltage or about spurious couplings of mythical
voltages like you can get with meters especially Digital meters.

Once in college Elec Eng Lab, a cotractor wanted to test 3 wires,
rubbed 2 together and closed down whole large building. when asked our
instructor agreed that was not the accepted method. :-?

--
John G Sydney.

[N_Cook]

Is it apochriphal? . I was told that civil engineering subcontractors,
laying new utilities water/sewage/electricity etc in trenches, would
confirm that any power cables they came across that should be dead ,
were dead or not.
Using a cartridge powered cutting blade , that was explosively shot
across the cable, severing it.

[jeanyves]

On 2015-07-10 14:42:06 +0000, KenO said:

> Hi,

>
> Am new to ESR Meters so have been searching the Internet and Forums for info.
>
> Appreciate comments from others that have been using ESR Meters as to
> what features would be included in an "Ideal ESR Meter"
>

> Thanks
>
> Ken

you should see all available on this repository, and then choose to buy
or build one
http://kripton2035.free.fr/esr-repository.html

best regards,
--

Jean-Yves.

[Cursitor Doom]

On Sun, 12 Jul 2015 18:41:57 -0700, jurb6006 wrote:

> To say the least, this is not enticing me to buy one. One kilohertzz
> square wave at 400 mV amplitude positive going, with a scope freewheeled
> into sync and DC coupled. The most effective lytic checker in the world
> once you lern to read it.

Hmmm. Your device is still going to switch on low barrier height diodes
like Schottkys and whatnot at that voltage level.

[Phil Allison]

Cursitor Doom wrote:

>
> > One kilohertzz
> > square wave at 400 mV amplitude positive going,
> > with a scope freewheeled into sync and DC coupled.
> > The most effective lytic checker in the world
> > once you lern to read it.
>
> Hmmm. Your device is still going to switch on low barrier height diodes
> like Schottkys and whatnot at that voltage level.

** So you think having an electro connected across the square generator will have NO effect on the output voltage ??

Got any idea of the impedance of a 100uF cap at 1kHz ??




... Phil

[Baron]

Phil Allison prodded the keyboard with:

I have two of those test bulbs ! I forget who made them. But if
there is really voltage there they don't lie.

--
Best Regards:
Baron.

[Dimitrij Klingbeil]

Yep, that instrument used to be called a "Kabelbeschußgerät" here in
Germany. Nowadays they fall under the firearms regulations, which made
them a royal pain in the back end to own and operate, so they're
actively being replaced by remote-operated pneumatic equivalents now.

Dimitrij

[M Philbrook]

In article <82f2ea2f-dc27-4e51...@googlegroups.com>,
jurb...@gmail.com says...

> > Just wait for it to fully boot or put some unknown charged cap on
> >the leads before switching it on. At least you can help them
> >to stay in business.
> >
> >Jamie "
>
> To say the least, this is not enticing me to buy one. One kilohertzz square wave at 400 mV amplitude positive going, with a scope freewheeled into sync and DC coupled. The most effective lytic checker in the world once you lern to read it.
>
> Once you learn to read it. I invented it, I used it to great profit and productivitly and I taught others how to use it, but only where I worked.

I doubt many much that you invented the process.

That trick dates back to the days of early electronics, very early..

> Now that I am older and ready to die Imight be tempted to reveal all the details. the bottom line is that tis thing read directly RIGHT NOW, no waiting for some stupid program to run. Like the one they had at opjne job, the son of a bitch sat there and said "DISCHARGING". The fuck you cre if it is charged ? Just read the AC resistance.
>
> Well my scope doodad does exactly that and if the cap is charged then the scope will still read correctly on AC and not iondicate the cap is charged. BTW, does it occur to anyone that IF the cap is charged that it holds a charge and therefore is probably good ? Or are you testing for 0.05 ohms of ESP in the filter caps of an audio amp and giving name to the term "audiophool" ?
>
> It is amazing they do not teach this. you put a signal to a device - the DUT - and then measure what is does. What is not simple about that ? God damn, I figured out this cap checker witht eh scope thing when I was about 16. ON MY OWN. Fuck Dick Smith. Well not really but you know what I mean. In fact I made a trade with Bob Parker. Some knobs for a Ysamaha receiver for an elcheapo boomerang. Hey, it came back a few times which proved it was not just a stick, but then
the kids got ahold of it and it was then a stick. Know what I mean ?

Back then it may have worked with out worry, most likely due to the
fact that many square wave generators were not able to generate the
raise time like they do today. There ware other things to consider now.

Jamie

[jurb...@gmail.com]

>"** So you think having an electro connected across the square generator will have NO effect on the output voltage ?? "

I wrote that wrong.

OK, the 1 KHz square wave I generally get from the probe calibrator but not all of them are compatible. They have to be more than 400 mV and less than 360 ohms source impedance, then I modify it to be 400 mV and 360 ohms souirce impedance.

This is wired directly to the vertical input and set for the top and bottom of the square wave to be equidistant from the center of the screen. The DUT shunts it.

You can tell the differenc between low and high value caps. A 100 uF generally results in a flat line if good. If it has ESR you will see some square wave still. Lower value caps are not as easy to read of course because they give you a quarter sine wave. However, remember you are ooking for the vertical parts of the trace. The fast rise and fall time indicates the ESR.

Try it, and get a bunch of caps and try it with resistors in series with the caps. When there is resistance there is a part of the trace with fast rise/fall times. THAT is excatly what you are looking for.

Another thing to remem,ber is that sme caps are more critical than others. I see where people simply change ALL of them in vintage audio equipment and that is very rarely ever needed. they say it sounds better and I do not disagree, but in most cases they would have gotten the same results by changing maybe a half dozen, rather than fifty of them.

I also got to the point where I didn't pay much attention in TVs anymore. My sister's PC monitor went down with someting like a 1,000 uF at 35 volts. I didn't have ANYTHING at the house at the time aand wanted to just see it work. I put a 100 uF at 160 volts in and it worked. I know that is ridiculous and I told her it is liable to fail soon. But I would get the right cap and put it in. So now I have some stock of caps, or electros as you like to call them and here it is like a YEAR later and that SOB still works.

TV, PC mobos and all that, I determine which caps are all in a bank. Alot of them use four, five, all in parallel. You only need ONE. So I put ONE in for test. Id on't even cut the leads, I reuse the same test caps over and over. If it works and I find out the pamel and the Tcon are good, then I proceed with a repair and change them. but I don''t wate them by changing them all and then have a bunch of caps in the drawer with the leads trimmed, like alot of assholes out there. That costs MONEY, and almost all businesses that are still in buisiness here are wo rkjing on a very small margin. You can't afford to waste parts even if they are only a dollar or two each. Hell, I am to the point of ratyioning solderwick. Seriously, I keep it in a puill bottle so it doesn't dry out and it only comes out when there is money involved.

>"Got any idea of the impedance of a 100uF cap at 1kHz ?? "

Ummm, damn I forget so much.

1 / 2 pi F C and then the vector sum of the ESR and ESL I think. Somnething like that. Don't you have the impedance nomograph ?

http://cjh.polyplex.org/electronics/nomograph/

It was gifted by someone on one of the sci.electronics newgroups. I, for one, appreciate it. It will save to your HD but I couldn't get it to run in Firefox right so it is saved in MHT format, which means my copy will only open in IE. You might have different results, or as they say YMMV.

I also started to design a small cap checker based on reading the fast rise and fall times of a square wave. Funny, I recently ran across it, on paper of course. If I design, I do it on paper. I am trying to learn Spice but it is aggravating at times. But seriously, if I ever buoold it it will do what I want. It will read caps both large and small and do it IMMEDIATELY with easily readable display on a simple (multiple for different frequencies) LED bar graph.

However I am not really impelled to finish it. The work I am doing now simply does not require any more advanced solutions than I alreay have. And what's more, that apply the waveform to the DUT thing has even more uses. I was trying to figure out one for inductors but haven't gone that far with that.

Bottom line, it just ain't worth it. I can tell with a scope all I nneed to know.

And BTW, where is Jerry G ? He croak on us or what ? We are in a fifteen year old thread here. Hell, back then we still had Jim Yanik. He is probably pushing up daisys as well. Lenny is still hanging in there. Ho many others are just gone ?

These Googlers who resurrect old threads might be a PITA, but really, now I am reminded of how this group used to be.

Tripped out.

[jurb...@gmail.com]

>"Hmmm. Your device is still going to switch on low barrier height diodes >like Schottkys and whatnot at that voltage level. "

Yes, but I am aware of that so it is alright. I did try to lower the applied voltage but then the scope picks up too much noise because I use regular voltmeter type probe for ease ot use.

The usual scope probe is simply inappropriate for checking caps like that. Plus the ground doesn't usually go to ground, like when checking coupling, rather than decoupling caps.

[jurb...@gmail.com]

>"Yep, that instrument used to be called a "Kabelbeschußgerät" here in
>Germany. Nowadays they fall under the firearms regulations, which made
>them a royal pain in the back end to own and operate, so they're
>actively being replaced by remote-operated pneumatic equivalents now. > >Dimitrij "

Damn shame about gun control. One of these days you might need one. Over here, there are about 50 million of us who will tar and feather any politician starts that shit. And BTW, while I am too old to learn a new language, I really like German. you guys can say in one word what it takes up a paragraph to say. Of course you got words with like 43 letters that we USians will never understand.

Like BMW or someone came out with a head design for a car engine - tricellular combustion chanber. Something likt that. Took three words in English to describe, German can do it in one. I like that.

[Cursitor Doom]

On Tue, 14 Jul 2015 12:44:05 -0700, jurb6006 wrote:

> I really like German. you guys can say in one word what it
> takes up a paragraph to say. Of course you got words with like 43
> letters that we USians will never understand.
>
> Like BMW or someone came out with a head design for a car engine -
> tricellular combustion chanber. Something likt that. Took three words in
> English to describe, German can do it in one. I like that.

Actually, the entire German language vocabulary is significantly smaller
than the English one. Germans don't have specific words for things like
you assume they do; they simply run separate words together by removing
the spaces in between, so by way of example in English, you would have
the warning sign: "treebranchfallingoffdanger" in public parks and such
like. This can make for some incredibly long and intimidating looking
words to foreigners who are unfamiliar with the practice.

[c4urs11]

Like Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz?

Cheers!

[Cursitor Doom]

On Tue, 14 Jul 2015 21:13:23 +0000, c4urs11 wrote:

> Like Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz?
>
> Cheers!

Genau! ;-)

[Clifford Heath]

On 15/07/15 05:31, jurb...@gmail.com wrote:
> http://cjh.polyplex.org/electronics/nomograph/
>
> It was gifted by someone on one of the sci.electronics newgroups.
> I, for one, appreciate it. It will save to your HD but I couldn't
> get it to run in Firefox right so it is saved in MHT format, which
> means my copy will only open in IE. You might have different results,
> or as they say YMMV.

Glad you like it. I enjoyed writing it. I'm surprised it doesn't work
in your Firefox though - it does for me, both from the web and from the
saved files. Are you sure you saved it correctly?

Clifford Heath.

[John Robertson]

Ah, but it seems that word (Rind...) no longer exists...

http://www.telegraph.co.uk/news/worldnews/europe/germany/10095976/Germany-drops-its-longest-word-Rindfleischeti....html

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

[N_Cook]

On 15/07/2015 05:24, John Robertson wrote:
> On 07/14/2015 2:40 PM, Cursitor Doom wrote:
>> On Tue, 14 Jul 2015 21:13:23 +0000, c4urs11 wrote:
>>
>>> Like Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz?
>>>
>>> Cheers!
>>
>> Genau! ;-)
>>
>
> Ah, but it seems that word (Rind...) no longer exists...
>
> http://www.telegraph.co.uk/news/worldnews/europe/germany/10095976/Germany-drops-its-longest-word-Rindfleischeti....html
>
>
> John :-#)#
>

And the Welsh place name
Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch
was artificially composed purely as a tourist trap.
I heard the english word
antisdisestablishmentarianism
validly used in a documentary a month back