I seem to be accumulating a pile of things with faults that are most
likely down to dodgy capacitors, but my homebrew ESR meter's one of those
things that is still in deep storage back in the UK. So...

1) I know that there was a thread a few weeks ago about ESR meters, and
someone suggested one that was being sold on ebay - I think that
listing's gone, but the site seems to be awash with others (all via
China) which I believe are exactly the same product (e.g. http://
tinyurl.com/ces3y7m). They all show a capacitor hooked directly to the
meter, though - so can anyone confirm that this meter is suitable for in-
circuit testing? (typically I think meters output a sine wave around
100kHz with an amplitude below that which will trip TTL logic gates, do
they not?)

2) Any other recommendations for a cheap meter? I really don't need
inductance, transistor testing etc. as my DMM does that anyway ,so just
plain ol' ESR will do.

3) Any recommendations for schematics for a DIY meter? I think I've got
at least one moving-coil meter in the junk box, and a few op-amps of
various types. I don't think I've got the schematic for the "in-storage"
meter that I built any more. There are quite a few schematics available
via google, but I don't know if any of them are any good or not...

cheers

Jules

In article ,
Jules Richardson wrote:
2) Any other recommendations for a cheap meter? I really don't need
inductance, transistor testing etc. as my DMM does that anyway ,so just
plain ol' ESR will do.

The cheap ESR and so on one off Ebay is rather better for basic transistor
checking than any of the DVMs etc I have - you don't need to identify the
transistor first. Just test it and the meter tells you the pin out, NPN or
PNP, as well as gain etc. Very useful, IMHO.

It seems to work on in circuit caps as well as my other ESR meter.

--
*Marathon runners with bad footwear suffer the agony of defeat*

Dave Plowman London SW
To e-mail, change noise into sound.

On Friday, March 29, 2013 5:46:10 PM UTC, Jules Richardson wrote:
I seem to be accumulating a pile of things with faults that are most

likely down to dodgy capacitors, but my homebrew ESR meter's one of those

things that is still in deep storage back in the UK. So...



1) I know that there was a thread a few weeks ago about ESR meters, and

someone suggested one that was being sold on ebay - I think that

listing's gone, but the site seems to be awash with others (all via

China) which I believe are exactly the same product (e.g. http://

tinyurl.com/ces3y7m). They all show a capacitor hooked directly to the

meter, though - so can anyone confirm that this meter is suitable for in-

circuit testing? (typically I think meters output a sine wave around

100kHz with an amplitude below that which will trip TTL logic gates, do

they not?)



2) Any other recommendations for a cheap meter? I really don't need

inductance, transistor testing etc. as my DMM does that anyway ,so just

plain ol' ESR will do.



3) Any recommendations for schematics for a DIY meter? I think I've got

at least one moving-coil meter in the junk box, and a few op-amps of

various types. I don't think I've got the schematic for the "in-storage"

meter that I built any more. There are quite a few schematics available

via google, but I don't know if any of them are any good or not...



cheers



Jules

Amazon £12-15, test L,C&ESR,R,etc


NT

On Fri, 29 Mar 2013 17:46:10 +0000 (UTC), Jules Richardson
wrote:


I seem to be accumulating a pile of things with faults that are most
likely down to dodgy capacitors, but my homebrew ESR meter's one of those
things that is still in deep storage back in the UK. So...

1) I know that there was a thread a few weeks ago about ESR meters, and
someone suggested one that was being sold on ebay - I think that
listing's gone, but the site seems to be awash with others (all via
China) which I believe are exactly the same product (e.g. http://
tinyurl.com/ces3y7m). They all show a capacitor hooked directly to the
meter, though - so can anyone confirm that this meter is suitable for in-
circuit testing? (typically I think meters output a sine wave around
100kHz with an amplitude below that which will trip TTL logic gates, do
they not?)

2) Any other recommendations for a cheap meter? I really don't need
inductance, transistor testing etc. as my DMM does that anyway ,so just
plain ol' ESR will do.

3) Any recommendations for schematics for a DIY meter? I think I've got
at least one moving-coil meter in the junk box, and a few op-amps of
various types. I don't think I've got the schematic for the "in-storage"
meter that I built any more. There are quite a few schematics available
via google, but I don't know if any of them are any good or not...

cheers

Jules

This looks like the one mentioned.
http://www.ebay.co.uk/itm/New-Transi...item51a99632dc

It doesn't mention in-circuit ESR testing but
I can't think of a reason why it wouldn't work in most cases.

--
Graham.

%Profound_observation%

In article ,
Jules Richardson writes:

I seem to be accumulating a pile of things with faults that are most
likely down to dodgy capacitors, but my homebrew ESR meter's one of those
things that is still in deep storage back in the UK. So...

I repair lots of things, but I haven't yet needed an ESR meter.
To test, I simply parallel up a new capacitor, and see if that
fixes the issue.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Fri, 29 Mar 2013 22:11:06 +0000, Andrew Gabriel wrote:

In article ,
Jules Richardson writes:

I seem to be accumulating a pile of things with faults that are most
likely down to dodgy capacitors, but my homebrew ESR meter's one of
those things that is still in deep storage back in the UK. So...

I repair lots of things, but I haven't yet needed an ESR meter.
To test, I simply parallel up a new capacitor, and see if that fixes the
issue.

Hmm, OK if there's the physical space to do so, or you have suitable
spares (and know that they're good!), and the item doesn't use too many,
and that the item can easily be tested without lots of reassembly etc.

I've got by without a meter for a few years now because all the cap
faults I've had in things have been obvious ones (leaks, bulging cases,
circuit [mis]behaviour pointing to a particular one etc.) - but just
lately I seem to have accumulated things where a meter would make life a
lot easier.

It's certainly not something that I'd use particularly often (and so
naturally don't want to spend a fortune on, either!) - but it'd be useful
to have one around.

cheers

Jules

"Andrew Gabriel" wrote in message
...
In article ,
Jules Richardson writes:

I seem to be accumulating a pile of things with faults that are most
likely down to dodgy capacitors, but my homebrew ESR meter's one of those
things that is still in deep storage back in the UK. So...

I repair lots of things, but I haven't yet needed an ESR meter.
To test, I simply parallel up a new capacitor, and see if that
fixes the issue.

+1
In 48 years I've never needed one. If I can't fix it with a DMM/AVO, scope,
logic analyser etc it either 'aint worth fixing or I'm incapable. Maybe it
depends on the type of kit you're playing with. Same as TDRs, never needed
to use one.

On Fri, 29 Mar 2013 23:58:13 -0000, "bm" wrote:


"Andrew Gabriel" wrote in message
...
In article ,
Jules Richardson writes:

I seem to be accumulating a pile of things with faults that are most
likely down to dodgy capacitors, but my homebrew ESR meter's one of those
things that is still in deep storage back in the UK. So...

I repair lots of things, but I haven't yet needed an ESR meter.
To test, I simply parallel up a new capacitor, and see if that
fixes the issue.

+1
In 48 years I've never needed one. If I can't fix it with a DMM/AVO, scope,
logic analyser etc it either 'aint worth fixing or I'm incapable. Maybe it
depends on the type of kit you're playing with. Same as TDRs, never needed
to use one.


I thought they were a gimmick un till I started to use one in a
workshop and I changed my mind pretty quickly.
It was a "Bob Parker" similar to the black one here
http://www.flippers.com/BlueEsr.html

although that page doesn't mention the laudable beep you hear if the
ESR is under a couple of ohms (forgot the exact figure.
If they have removed that feature it's a big mistake IMHO.
You can test in circuit with the power off. Saves a lot of time, and
time = money

--
Graham.

%Profound_observation%

In article ,
Andrew Gabriel wrote:
In article ,
Jules Richardson writes:

I seem to be accumulating a pile of things with faults that are most
likely down to dodgy capacitors, but my homebrew ESR meter's one of
those things that is still in deep storage back in the UK. So...

I repair lots of things, but I haven't yet needed an ESR meter. To test,
I simply parallel up a new capacitor, and see if that fixes the issue.

Not much use with tantalum which can fail short circuit. ;-)

Checking a suspect cap with an ESR meter is so much quicker than by
substitution, etc. I'd say it's one of those things you may not miss if
you've never had one.

My Bob Parker kit one was pretty expensive, but still paid for itself.
They're a lot cheaper now with even cheaper alternatives.

--
*It doesn't take a genius to spot a goat in a flock of sheep *

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
"Dave Plowman (News)" writes:
In article ,
Andrew Gabriel wrote:
In article ,
Jules Richardson writes:

I seem to be accumulating a pile of things with faults that are most
likely down to dodgy capacitors, but my homebrew ESR meter's one of
those things that is still in deep storage back in the UK. So...

I repair lots of things, but I haven't yet needed an ESR meter. To test,
I simply parallel up a new capacitor, and see if that fixes the issue.

Not much use with tantalum which can fail short circuit. ;-)

Checking a suspect cap with an ESR meter is so much quicker than by
substitution, etc. I'd say it's one of those things you may not miss if
you've never had one.

I didn't say by substitution - I usually just touch the leads of a new
one against the existing one's leads. If it's a mains circuit, I might
temporarily solder it to the existing cap's solder pads on the underside
of the circuit board so I'm not holding it.

My Bob Parker kit one was pretty expensive, but still paid for itself.
They're a lot cheaper now with even cheaper alternatives.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

"Andrew Gabriel" wrote in message
...
In article ,
"Dave Plowman (News)" writes:
In article ,
Andrew Gabriel wrote:
In article ,
Jules Richardson writes:

I seem to be accumulating a pile of things with faults that are most
likely down to dodgy capacitors, but my homebrew ESR meter's one of
those things that is still in deep storage back in the UK. So...

I repair lots of things, but I haven't yet needed an ESR meter. To test,
I simply parallel up a new capacitor, and see if that fixes the issue.

Not much use with tantalum which can fail short circuit. ;-)

Checking a suspect cap with an ESR meter is so much quicker than by
substitution, etc. I'd say it's one of those things you may not miss if
you've never had one.

I didn't say by substitution - I usually just touch the leads of a new
one against the existing one's leads. If it's a mains circuit, I might
temporarily solder it to the existing cap's solder pads on the underside
of the circuit board so I'm not holding it.

As Dave says with tants, that's all very well unless the cap has gone short.
Whilst I know it's not definitive, the fact that a decent ESR meter is also
a low ohms meter, if you hang it across a 47uF cap, and see a reading of
0.02 ohms, there's a very good chance that it is short circuit, and not just
an exceptionally good cap, ESR-wise. A quick dab across the legs with a good
old AVO, then confirms this. About the only thing that I would say about
using an ESR meter, is that a degree of experience with them has to be built
up. That's how you would know, for instance, that a reading of 0.02 ohms for
a 47uF cap would be wrong, but could well be right for a decent 10000uF cap.
Each to his own, I guess, but I don't think I have ever come across an
engineer that hasn't sworn by his ESR meter, once he's actually been out and
got one, and put it to commercial use. If anything happened to mine, it
would be like cutting my arm off ...

Arfa



My Bob Parker kit one was pretty expensive, but still paid for itself.
They're a lot cheaper now with even cheaper alternatives.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Mar 30, 3:38*pm, "Arfa Daily" wrote:

got one, and put it to commercial use. If anything happened to mine, it
would be like cutting my arm off ...

Arfa


+1

On 29/03/2013 23:58, bm wrote:
+1
In 48 years I've never needed one. If I can't fix it with a DMM/AVO, scope,
logic analyser etc it either 'aint worth fixing or I'm incapable. Maybe it
depends on the type of kit you're playing with. Same as TDRs, never needed
to use one.

I've never had a TDR, but several times wished I did. It would have been
really nice in the days of thinnet to be able to press a button and get
an idea of which plonker had undone the t-piece, and if that wasn't
enough to binary chop until I had him.

Luckily I've never been full time networks

Andy

In article ,
Andy Champ writes:
On 29/03/2013 23:58, bm wrote:
+1
In 48 years I've never needed one. If I can't fix it with a DMM/AVO, scope,
logic analyser etc it either 'aint worth fixing or I'm incapable. Maybe it
depends on the type of kit you're playing with. Same as TDRs, never needed
to use one.

I've never had a TDR, but several times wished I did. It would have been
really nice in the days of thinnet to be able to press a button and get
an idea of which plonker had undone the t-piece, and if that wasn't
enough to binary chop until I had him.

Likewise.
I wrote the ethernet driver for a minicomputer many decades ago.
When I got the jammed flag set (implying a shorted or open circuit
cable generating reflections on every transmit attempt), I reported
the internal TDR value recorded by the AMD LANCE chipset. It somewhat
surprises me that no other ethernet driver I ever saw reported this
most useful information. The resolution wasn't great, but it was
loads better than having nothing. Several customers told me that
when their company ethernet went down, they'd go over to the console
of their GEC4000 and look to see how far the cable fault was from it.

Luckily I've never been full time networks

Andy

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Wed, 03 Apr 2013 09:08:11 +0000, Huge wrote:

On 2013-04-03, Andrew Gabriel wrote:

I wrote the ethernet driver for a minicomputer many decades ago. When I
got the jammed flag set (implying a shorted or open circuit cable
generating reflections on every transmit attempt), I reported the
internal TDR value recorded by the AMD LANCE chipset. It somewhat
surprises me that no other ethernet driver I ever saw reported this
most useful information.

It's all part of the "useless error message" syndrome, which started
with mainframe ABENDs and huge core dumps and culminated with Lotus
Notes reporting "There is an error. [OK]"

We had a 'home grown' operating system running on our ICL mainframe (dual
CPU, SMP, 2960) for years. Previously it had run an appallingly
unreliable ICL operating system.

The hardware wasn't great, and we had a nice reporting system whenever
there was a single bit recovered memory error. The raw information was
dumped into a log file and later analysed. Once a day it generated a
report telling the engineers of problematical memory boards, and which
chip was marginal. (the ICL system had just ignored the recovered errors
until they became multi-bit and the system crashed)

It did take a while to convince the engineers that the system actually
worked!




--
Use the BIG mirror service in the UK: http://www.mirrorservice.org
My posts (including this one) are my copyright and if @diy_forums on
Twitter wish to tweet them they can pay me £30 a post
*lightning surge protection* - a w_tom conductor

In article ,
Andy Champ wrote:
On 29/03/2013 23:58, bm wrote:
+1 In 48 years I've never needed one. If I can't fix it with a
DMM/AVO, scope, logic analyser etc it either 'aint worth fixing or I'm
incapable. Maybe it depends on the type of kit you're playing with.
Same as TDRs, never needed to use one.

I've never had a TDR, but several times wished I did. It would have been
really nice in the days of thinnet to be able to press a button and get
an idea of which plonker had undone the t-piece, and if that wasn't
enough to binary chop until I had him.

Luckily I've never been full time networks

Wot's a TDR?

--
*In some places, C:\ is the root of all directories *

Dave Plowman London SW
To e-mail, change noise into sound.

In message , "Dave Plowman (News)"
writes
In article ,
Andy Champ wrote:
On 29/03/2013 23:58, bm wrote:
+1 In 48 years I've never needed one. If I can't fix it with a
DMM/AVO, scope, logic analyser etc it either 'aint worth fixing or I'm
incapable. Maybe it depends on the type of kit you're playing with.
Same as TDRs, never needed to use one.

I've never had a TDR, but several times wished I did. It would have been
really nice in the days of thinnet to be able to press a button and get
an idea of which plonker had undone the t-piece, and if that wasn't
enough to binary chop until I had him.

Luckily I've never been full time networks

Wot's a TDR?

http://en.wikipedia.org/wiki/Time-domain_reflectometer


Invaluable for finding cable faults in large buildings and beyond.

I keep a simple one
http://www.norbain.co.uk/downloads/d...structions.PDF
for checking CCTV cabling and have used others on 100V line PA, I had
500m+ of cabling at an Open Golf course a few years ago that had gone
short and being in a hurry grabbed the nearest BT engineer and persuaded
him to lend me his TDR for a couple of minutes, it took me to within
feet of the cable. The inaccuracy was probably down to my pacing out of
the distance!

When my neighbours electric supply failed a few years ago the leccy
board opened up a joint in the pavement and TDR'd the underground cable
to his house and found the break within a foot of where they thought it
was, a brick used as infill 50 years before had finally damaged the
cable.

So all in all a very useful bit of kit.
--
Bill

In article ,
Bill wrote:
Wot's a TDR?

http://en.wikipedia.org/wiki/Time-domain_reflectometer

Ah - sort of know what that is but didn't know the name.



Invaluable for finding cable faults in large buildings and beyond.

I keep a simple one
http://www.norbain.co.uk/downloads/d...structions.PDF
for checking CCTV cabling and have used others on 100V line PA, I had
500m+ of cabling at an Open Golf course a few years ago that had gone
short and being in a hurry grabbed the nearest BT engineer and persuaded
him to lend me his TDR for a couple of minutes, it took me to within
feet of the cable. The inaccuracy was probably down to my pacing out of
the distance!

When my neighbours electric supply failed a few years ago the leccy
board opened up a joint in the pavement and TDR'd the underground cable
to his house and found the break within a foot of where they thought it
was, a brick used as infill 50 years before had finally damaged the
cable.

So all in all a very useful bit of kit.

I've got one of those things that sends an RF signal up a cable and you
trace it with a receiver. Was very useful on the one occasion I needed it.

But the ESR meter gets much more frequent use. ;-)

--
*If a thing is worth doing, wouldn't it have been done already?

Dave Plowman London SW
To e-mail, change noise into sound.

In message , "Dave Plowman (News)"
writes
In article ,
Bill wrote:
Wot's a TDR?

http://en.wikipedia.org/wiki/Time-domain_reflectometer

Ah - sort of know what that is but didn't know the name.
So all in all a very useful bit of kit.


I've got one of those things that sends an RF signal up a cable and you
trace it with a receiver. Was very useful on the one occasion I needed it.


I tend to use one of the ones that injects a high level of audio into
the wiring and then trace it with a handheld detector, my current one
gives a rather spooky warble, great when used in the basements of old
mansion houses! :-) Also the detector makes a good mains cable
detector too.


But the ESR meter gets much more frequent use. ;-)

After all the discussion on ESR meters here, I am planning on adding one
to my kit.


--
Bill