John Larkin wrote:

The problem with all these circuits is the simplicity of the meter
needle: it can't untangle the inductive, capacitive, and resistive
components. If I were routinely repairing stuff that may have bad
caps, I'd build a scope probe that injected a square wave current
into the tip and displayed the result on the scope, with
switchable frequency between, say, 1 KHz and 100 KHz. The scope
vertical gain switch adds a lot of rangeability. This could be
useful for all sorts of things, not just caps. Diodes, too!

--- esl
/\ --------
/ \ /
/ \ ------- slope = 1/C
/ \ /
/ ------ -- esr
-----------

John

If you are repairing equipment, you need a fast Go/NoGo test.
Injecting a square wave into a cap generates complex waveforms that
are difficult to separate and measure. Using a scope would really
slow things down. You need the simplicity of a meter needle or even
a two-color LED.

Contrary to your claims about the bridge configuration, as I showed
in my reply to John J., this configuration removes the di/dt spike
from the output waveform and leaves only the ESR and I*dt
components. See the LTspice file I posted that shows this.

Since it can test in-circuit due a low test amplitude that won't
turn on semiconductor junctions, has built-in detection for shorted
caps, and can be protected against fully-charged capacitors, it is
probably the fastest method available to detect bad caps in-circuit
or on the bench.

The ESR test range appears to be about 20X to 1/20 of the lower
bridge resistance. With a bridge resistance of 1 ohm, this covers
from about 20 ohms to perhaps 50 milliohms.

Trying to measure lower values of ESR with a square wave becomes
very problematic due to the di/dt spike and the I * dt ramp. I'd say
around 50 milliohms ESR is about the bottom limit for these methods.

To go lower, I'd use the network analyzer approach with a Kelvin
measurement across the cap to ground, and locate the series
resonance point. This techinque is described in numerous articles on
the web, and allows measuring very low values of ESR.

Regards,

Mike Monett

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks






"Mike Monett" wrote in message
...
Mike Monett wrote:

The original circuit is functional and provides very important
features that your circuit lacks.

I almost forgot. The original circuit applies a maximum of 0.1V peak
to the capacitor under test. This is low enough so the polarity is
not important. It will not turn on semiconductor junctions, so most
capacitors may be tested in-circuit.

Your version applies 2.5VDC to the capacitor. This means the cap
must be unsoldered from the circuit, tested, then re-soldered back
in the circuit. This takes time and risks damage to the cap and pcb.

Also, the 2.5VDC means the user must observe polarity on low-voltage
caps. This adds complexity and increases the difficulty of use.

These are significant design flaws.

Regards,

Mike Monett

To complete the record, here is the LTspice files for John J. and
John L.'s ESR measuring circuits. The capacitor parameters are
chosen to resonate at 100KHz, which is also the test frequency.

As can be seen in the transient analysis, there is no evidence of
orthogonal or quadrature components in the output signal.

The reason is the external circuit resistance completely swamps the
internal ESR. The external circuit determines the current through
the series network, so there is no energy transferred back and forth
between the capacitive and inductive components, thus no phase shift
between them.

The output signal is simply the di/dt from the ESL, I*dt from the
capacitor, and I*ESR, which is what we are trying to measure. Both
approaches give almost identical results.

You can change the component values in the .param list. As can be
seen, the inductive spike is very sensitive to risetime. Trying to
measure ESR below about 50 milliohms becomes very problematic with
these approaches.

As shown in the parent post, the bridge approach removes the
inductive spike, but it leaves the capacitor charging ramp. So it
also begins to fail below about 50 milliohms ESR.

However, the bridge approach allows in-circuit testing,
automatically detects shorted capacitors, and is insensitive to the
polarity of the capacitor.

Here is the LTspice ASC file:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~
Version 4
SHEET 1 880 708
WIRE -64 -48 -592 -48
WIRE -32 -48 -64 -48
WIRE -736 16 -800 16
WIRE -592 16 -592 -48
WIRE -592 16 -656 16
WIRE -544 16 -592 16
WIRE -448 16 -480 16
WIRE -336 16 -368 16
WIRE -224 16 -256 16
WIRE -800 32 -800 16
WIRE -224 32 -224 16
WIRE -800 128 -800 112
WIRE -688 304 -800 304
WIRE -576 304 -608 304
WIRE -544 304 -576 304
WIRE -512 304 -544 304
WIRE -496 304 -512 304
WIRE -400 304 -432 304
WIRE -288 304 -320 304
WIRE -176 304 -208 304
WIRE -64 304 -176 304
WIRE -32 304 -64 304
WIRE -576 320 -576 304
WIRE -512 384 -512 304
WIRE -480 384 -512 384
WIRE -352 384 -400 384
WIRE -176 384 -176 304
WIRE -176 384 -352 384
WIRE -800 400 -800 384
WIRE -352 400 -352 384
WIRE -576 416 -576 400
WIRE -400 416 -416 416
WIRE -416 432 -416 416
WIRE -512 464 -512 384
WIRE -400 464 -512 464
WIRE -352 496 -352 480
FLAG -800 400 0
FLAG -64 304 Jardine
FLAG -576 416 0
FLAG -416 432 0
FLAG -352 496 0
FLAG -64 -48 Larkin
FLAG -224 32 0
FLAG -800 128 0
FLAG -544 304 Vin
SYMBOL res -592 304 R0
SYMATTR InstName R2
SYMATTR Value 1e6
SYMBOL res -592 288 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R3
SYMATTR Value 180
SYMBOL Voltage -800 288 R0
WINDOW 0 42 44 Left 0
WINDOW 3 -41 151 Left 0
WINDOW 123 15 130 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V2
SYMATTR Value PULSE(4 -4 0 {Tr} {Tr} 5u 10u)
SYMBOL cap -432 288 R90
WINDOW 0 0 32 VBottom 0
WINDOW 3 32 32 VTop 0
SYMATTR InstName C1
SYMATTR Value {C}
SYMBOL res -304 288 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R1
SYMATTR Value {ESR}
SYMBOL ind -304 320 R270
WINDOW 0 32 56 VTop 0
WINDOW 3 5 56 VBottom 0
SYMATTR InstName L1
SYMATTR Value {L}
SYMBOL E -352 384 R0
WINDOW 0 38 42 Left 0
WINDOW 3 36 69 Left 0
SYMATTR InstName E1
SYMATTR Value 1e5
SYMBOL res -384 368 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R4
SYMATTR Value 100
SYMBOL res -640 0 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R6
SYMATTR Value 180
SYMBOL cap -480 0 R90
WINDOW 0 0 32 VBottom 0
WINDOW 3 32 32 VTop 0
SYMATTR InstName C2
SYMATTR Value {C}
SYMBOL res -352 0 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R7
SYMATTR Value {ESR}
SYMBOL ind -352 32 R270
WINDOW 0 32 56 VTop 0
WINDOW 3 5 56 VBottom 0
SYMATTR InstName L2
SYMATTR Value {L}
SYMBOL Voltage -800 16 R0
WINDOW 0 42 44 Left 0
WINDOW 3 21 103 Left 0
WINDOW 123 15 130 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value PULSE(0 4 0 {Tr} {Tr} 5u 10u)
TEXT -528 -208 Left 0 ;'ESR Measuring Circuits
TEXT -856 -152 Left 0 !.param C = 100uF\n.param L = 2.5330295910584E-
08\n.param ESR = 0.05\n.param Tr = 100n
TEXT -816 192 Left 0 ;NOTE:\nR2 was 1 ohm in the original. It is at
virtual ground and has little effect on the circuit. \nR4 was 56k in the
original. Reduced to 100 ohm to reduce settling time for transient
analysis.
TEXT -856 -184 Left 0 !.tran 0 100.1m 100m 250n

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~
Here is the PLT file:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~
[Transient Analysis]
{
Npanes: 2
{
traces: 1 {524292,0,"V(jardine)"}
X: ('µ',0,0,1e-005,9.99998048950707e-005)
Y[0]: ('m',0,0.03,0.002,0.058)
Y[1]: ('_',0,1e+308,0,-1e+308)
Volts: ('m',0,0,0,0.03,0.002,0.058)
Log: 0 0 0
GridStyle: 1
},
{
traces: 1 {524290,0,"V(larkin)"}
X: ('µ',0,0,1e-005,9.99998048950707e-005)
Y[0]: (' ',3,2.025,0.001,2.039)
Y[1]: ('_',0,1e+308,0,-1e+308)
Volts: (' ',0,0,3,2.025,0.001,2.039)
Log: 0 0 0
GridStyle: 1
}
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~

Regards,

Mike Monett

"Mike Monett" wrote in message
...

"john jardine" wrote:

John Larkin wrote:

Something roughly like this, maybe. This is a 2-minute hack, so
don't jump all over it right away; a real design would take more
time.

Basically, it's an oscillator that dumps current into the cap,
and a synchronous detector to remove most of the orthogonal
component. It ain't perfect, but should be a lot better than a
scalar measurement.

John

This was built along similar lines. The synchronous rectification
is not perfect due to phase shift in the forward signal path but
the arrangement is useful for reducing the annoying capacitive
quadrature component from Q's up to about 3 (at the 100kHz). It's
usable down to the milliohm area and proved the (cheap) 1000 off
10uF cap's I bought, had an ESR of between 1 and 3 ohms!.


Hi John,

Do you mind if I make some comments?
[my pleasure Mike :] The 1 ohm resistor, R5, can be
removed from the circuit. It is at a virtual ground node and has
little or no voltage across it. So removing it has little effect on
the circuit.

Can't lose the 1 ohm as the other ranges need it. If you look at the feed
current you'll notice with the 1 ohm either in or out, the current to the
virtual earth is the same at 20ma. So the 4V signal, 180 ohms has the
same drive effect as 20mV, 1 ohm. Switch and wiring hence kept simple.

With R5 gone, and the ESR range switch in the 1 ohm position, the
180 ohm resistor, R4, is effectively in series with the capacitor
under test. The op amp merely changes the location of the ground
node, and inverts the output signal polarity.

I'm puzzled. The 180 ohm sees only 0V (the V.E.). The capacitor sees
similarly. Currents essentially isolated. Phase changes notified by opamp
output voltage.

Since R4 (180 ohms) is now in series with the capacitor, it
completely swamps out the internal ESR (0.05 ohms.) This means the
series combination of C, L, and R has negligible "Q", and there is
no quadrature or orthogonal component in the circuit.
However, as the ESR decreases, the corresponding voltage drop that
we are trying to measure also decreases. We no are faced with the
problem that the di/dt from the inductor is much larger than the I*R
drop from the ESR. This means the leading and trailing edge of the
square wave have large spikes.

For some reason LTspice is refusing your .asc text list, so I can't picture
where that 'L' and 180 ohms are. Can you repost it as a pic' somehow?.
I had a play with my unit and it is sensitive to (a lot) of added series
inductance. There's a 5% reading change with 2 foot of coiled test leads
(about 200nH). This is basically a 'ring down' (70MHz) at the opamp output
and seems related to the opamp stability (the THS is something like 150MHz
GB).
On the 1 ohm range it is surprisingly difficult to add noticable test
inductance without adding serious amounts of lead/wire resistance.
Essentially the meter is reading lead resistance with a bit of
capacitor ESR thrown in.
[Poly cap and s/c link. actual Vout -.063V. Link replaced with 1206 0.01ohms
and Vout=0.052V].
As test I've looked for inductive 'spikes' using the 'scope and about 20
different test capacitors (good through to rubbish). I saw nothing
untowards.
Presumably confirming that capacitors are not inductive (other than the
trivial effect of their leads and the test socket wiring).

If you used a diode peak detector to measure the amplitude, it would
respond as best it could to the leading edge spike, which would make
it impossible to measure the drop across the ESR. Your circuit and
Larkin's share this problem.

Using a synchronous rectifier helps a bit, but you are now faced
with trying to turn it on after the leading edge spike, and to turn
it off before the trailing edge spike. That could be tricky.

The test spikes I forced were a transient effect and only occupied a few %
of each complete cycle. Yes, a peak detector (without windowing) would have
severe problems on such a waveform. The niceness of the PSR is that it
can take on allcomers and average the spike energy out over each full
cycle.
It's not exact, as there's a 15% reading error with Qs up at 2.5. The opamp
clips at Q=3 but these are good quality poly' capacitors.

I spent this afternoon looking at these problems in SPICE,

Luxury!. I had a bad cap' problem. Result was a ESR meter. Cost me a day to
design and build. I've only used the damned thing once in the past year

and have
come to an amazing observation. There is a hidden but very
significant feature in the bridge ESR circuit referred to at the
beginning of this thread. The links a

1. Talino Tribuzio's page, showing the circuit from Nuova
Elettronica:

http://www.qsl.net/iz7ath/web/02_bre..._esr/index.htm

2. Gintaras' web page, who refers to Tribuzio's page in his readme

http://alytus.auksa.lt/esr/

The schematic is at

http://alytus.auksa.lt/esr/esr_meter_schematic.pdf

The valuable hidden feature is the bridge configuration completely
eliminates the leading and trailing edge spikes due to the capacitor
internal inductance. Since the spikes are in phase with the square
wave signal on the other side of the bridge, they simply disappear
at the output of the op amp!

This means the peak detector has a very clean square wave to work
with, and it can give a much more accurate measurement of the
signal. There is no tricky timing to fiddle with that can go out of
whack just when you need to use the tester.

If you like, I can post the analysis of your circuit and Larkin's
version showing the huge spikes that appear as the ESR becomes
smaller, and the triangular wave from the capacitance charging and
discharging. I don't really see a good way of overcoming these
problems.

As I mentioned in previous posts, the bridge circuit has significant
advantages, including low test voltage, in-circuit test, shorted
capacitor detect, etc. With the extremely clean output signal into
the peak detector, it becomes the obvious choice for hassle-free ESR
measurements.

I'll post the LTspice ASC file here along with the PLT file so you
can see how it works. I changed the bridge resistance to lower
values to allow measuring lower values of ESR.

[...]

Regards,

Mike Monett





--
Posted via a free Usenet account from http://www.teranews.com

lurk wrote:

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks


The schematic is online. It took all of three seconds to find it:
http://bama.edebris.com/manuals/creative/esr


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

"J.P." wrote:

You legal bunch of mumbo jumbo fails to prove anything to me. I simply
posted a goddamn schematic in a binary news group for the users there
to look at and maybe use and you and your gay sock puppet buddy have
gone on the attack for no reason. If you were half as intelligent as
you try and protray, you would know that the spirit of this posted
file was not intended to waste bandwidth with blowhard facts and mean
spirited abuses. And you are supposedly from the south? Where is your
graciousness Mr. Jackass? You have none. So you are that occassional
chick**** minded asshole that was the latrine maintence private with a
**** attitude and scowl to match. Take your hate and gay sockpuppet
and stuff them both up your sloppy ass dickweed. Suck down another 12
pack and make up 12 more reasons why the government ****ed you around
in the war and why you are now justified blaming everyone else for
your self created misery. Maybe you can cheat your rock star whore out
of another rock and feel like a hero again...see ya superfly...buzz
off


Of course it didn't prove anything, other than your claims of it being
"Invented" was a blatant lie. I don't drink any alcohol, but it ;looks
like its already destroyed what little mind you had.

Its really sad, Jane. I guess that all that booze, homemade drugs and
excessive intake of female hormones have pretty much destroyed your
sorry excuse for a life. Its obvious to everyone on the newsgroup that
you're illiterate.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

John Larkin wrote:

The problem with all these circuits is the simplicity of the meter
needle: it can't untangle the inductive, capacitive, and resistive
components. If I were routinely repairing stuff that may have bad
caps, I'd build a scope probe that injected a square wave current into
the tip and displayed the result on the scope, with switchable
frequency between, say, 1 KHz and 100 KHz. The scope vertical gain
switch adds a lot of rangeability. This could be useful for all sorts
of things, not just caps. Diodes, too!

--- esl
/\ --------
/ \ /
/ \ ------- slope = 1/C
/ \ /
/ ------ -- esr
-----------

John


http://members.ozemail.com.au/~bobpar/esrmeter.htm is one of the most
popular ESR meters in the electronics service industry.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

thanks.....dick smith makes one but is it like the creative electronics
one ?




"Michael A. Terrell" wrote in message
...
lurk wrote:

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks


The schematic is online. It took all of three seconds to find it:
http://bama.edebris.com/manuals/creative/esr


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

lurk wrote:

thanks.....dick smith makes one but is it like the creative electronics
one ?

"Michael A. Terrell" wrote in message
...
lurk wrote:

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks


The schematic is online. It took all of three seconds to find it:
http://bama.edebris.com/manuals/creative/esr

http://members.ozemail.com.au/~bobpar/esrmeter.htm

No, the DSE ESR meter is dugital, and works a lot better on the low
ESR caps in switch mode power supplies. It reads from .01 ohms to 100
ohms on the digital display, and has an automatic zeroing, if the test
leads are clipped together when its turned on. I have, and use the
DSE. I've tried the Creative, but it was almost useless to troubleshoot
the CPU power supplies on computer motherboards

The Creative is analog, with all the low ESR readings cramped
together at the end of the scale.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

On Mon, 09 Jul 2007 23:22:21 GMT, "Michael A. Terrell"
wrote:

lurk wrote:

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks


The schematic is online. It took all of three seconds to find it:
http://bama.edebris.com/manuals/creative/esr

Ghastly!

John

John Larkin wrote:

On Mon, 09 Jul 2007 23:22:21 GMT, "Michael A. Terrell"
wrote:

lurk wrote:

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks


The schematic is online. It took all of three seconds to find it:
http://bama.edebris.com/manuals/creative/esr

Ghastly!

John


You should see how they work. I can't undersand the fascination with
this old design. It is usless on modern high capacity, low ESR
electrolytics. I ran into the guy that owns the biggest TV shop in the
area a while back, while waiting to renew my truck tag. Since we were
in line over an hour, we started talking electronics. He'd never heard
of the DSE ESR meter, so I offered to stop by and show him mine. He let
one of his techs compare it to their Creative Electronics ESR meter, and
ordered two DSE ESR meter kits before I left their shop.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

On Mon, 09 Jul 2007 23:27:07 GMT, "Michael A. Terrell"
wrote:

"J.P." wrote:

You legal bunch of mumbo jumbo fails to prove anything to me. I simply
posted a goddamn schematic in a binary news group for the users there
to look at and maybe use and you and your gay sock puppet buddy have
gone on the attack for no reason. If you were half as intelligent as
you try and protray, you would know that the spirit of this posted
file was not intended to waste bandwidth with blowhard facts and mean
spirited abuses. And you are supposedly from the south? Where is your
graciousness Mr. Jackass? You have none. So you are that occassional
chick**** minded asshole that was the latrine maintence private with a
**** attitude and scowl to match. Take your hate and gay sockpuppet
and stuff them both up your sloppy ass dickweed. Suck down another 12
pack and make up 12 more reasons why the government ****ed you around
in the war and why you are now justified blaming everyone else for
your self created misery. Maybe you can cheat your rock star whore out
of another rock and feel like a hero again...see ya superfly...buzz
off


Of course it didn't prove anything, other than your claims of it being
"Invented" was a blatant lie. I don't drink any alcohol, but it ;looks
like its already destroyed what little mind you had.

Its really sad, Jane. I guess that all that booze, homemade drugs and
excessive intake of female hormones have pretty much destroyed your
sorry excuse for a life. Its obvious to everyone on the newsgroup that
you're illiterate.
Does you mother know you suck dicks? **** off fake asshole...

On Tue, 10 Jul 2007 05:04:52 GMT, the renowned "Michael A. Terrell"
wrote:

lurk wrote:

thanks.....dick smith makes one but is it like the creative electronics
one ?

"Michael A. Terrell" wrote in message
...
lurk wrote:

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks


The schematic is online. It took all of three seconds to find it:
http://bama.edebris.com/manuals/creative/esr

http://members.ozemail.com.au/~bobpar/esrmeter.htm

No, the DSE ESR meter is dugital, and works a lot better on the low
ESR caps in switch mode power supplies. It reads from .01 ohms to 100
ohms on the digital display, and has an automatic zeroing, if the test
leads are clipped together when its turned on. I have, and use the
DSE. I've tried the Creative, but it was almost useless to troubleshoot
the CPU power supplies on computer motherboards

Isn't the DSE one basically an impedance meter though?

The Creative is analog, with all the low ESR readings cramped
together at the end of the scale.

What good/bad level are you typically looking for?


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

"J.P." wrote:

Does you mother know you suck dicks? **** off fake asshole...


My mother is long dead, and you're the one who is always talking
about being gay and sucking dicks. As William Shakesphere said, "He
doth protest too much.". Quit projecting your lifestyle onto others.

To borrow a line from "Saturday Night Live": "Jane, you ignorant
slut!" You're the one who startedted slinging insults, but its obviuos
that you're incapable of handling the results. Go away while you have
any dignity left, and take your crap with you. Your pimp yelling for
you, you lazy bitch.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Spehro Pefhany wrote:

On Tue, 10 Jul 2007 05:04:52 GMT, the renowned "Michael A. Terrell"
wrote:

lurk wrote:

thanks.....dick smith makes one but is it like the creative electronics
one ?

"Michael A. Terrell" wrote in message
...
lurk wrote:

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks


The schematic is online. It took all of three seconds to find it:
http://bama.edebris.com/manuals/creative/esr

http://members.ozemail.com.au/~bobpar/esrmeter.htm

No, the DSE ESR meter is dugital, and works a lot better on the low
ESR caps in switch mode power supplies. It reads from .01 ohms to 100
ohms on the digital display, and has an automatic zeroing, if the test
leads are clipped together when its turned on. I have, and use the
DSE. I've tried the Creative, but it was almost useless to troubleshoot
the CPU power supplies on computer motherboards

Isn't the DSE one basically an impedance meter though?


Probably. It is microprocessor based, but it works. The fact that
it reads to .01 ohm allows you to test those damn 6.3 VDC electrolytics
used on motherboards. I preferred the Sencore Z-meter I used about 20
years ago, but I simply can't afford one.


The Creative is analog, with all the low ESR readings cramped
together at the end of the scale.

What good/bad level are you typically looking for?


Personally, I consider them bad if its more than 10% above the OEM
specifications, but you can't find specs for a lot of the crappy
electrolytics used on motherboards.

The ability to compare all the electrolytics on a bad board give you
some idea of what they were. Usually, the board quits working before
all the caps die. I just make sure the new cap specifications are
better than the lowest cap pulled from the board. Its hard to find GOOD
105 degree low ESR electrolytics in small quantities, and I've used up
all the new caps that I had on hand. I have a pile of fairly new
motherboards with bulging electrolytics that may just go to a local
recycler.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

DSE..... is that dick smith eletronics ? might do the paypal thing.....I'm
impressed with his esr meters.....thanks again Dave



"Michael A. Terrell" wrote in message
...
John Larkin wrote:

On Mon, 09 Jul 2007 23:22:21 GMT, "Michael A. Terrell"
wrote:

lurk wrote:

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like
the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks


The schematic is online. It took all of three seconds to find it:
http://bama.edebris.com/manuals/creative/esr

Ghastly!

John


You should see how they work. I can't undersand the fascination with
this old design. It is usless on modern high capacity, low ESR
electrolytics. I ran into the guy that owns the biggest TV shop in the
area a while back, while waiting to renew my truck tag. Since we were
in line over an hour, we started talking electronics. He'd never heard
of the DSE ESR meter, so I offered to stop by and show him mine. He let
one of his techs compare it to their Creative Electronics ESR meter, and
ordered two DSE ESR meter kits before I left their shop.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Spehro Pefhany wrote:
On Tue, 10 Jul 2007 14:42:41 GMT, the renowned "Michael A. Terrell"
wrote:

Digikey carries "low impedance" electrolytics in typical values (like
1000uF/6.3V/0.09 ohm/105°C for 28 cents ea. in 10's) but they might be
bigger than the ones used on some mobos. EEU-FC0J102

True, but what they don't seem to have are the United ChemCon Oxi caps, which
is what the motherboards use. Oxicaps are about 1/10th the ESR of the
very best aluminum electrolytics.

-Chuck

Spehro Pefhany wrote:

On Tue, 10 Jul 2007 14:42:41 GMT, the renowned "Michael A. Terrell"
wrote:

Spehro Pefhany wrote:

On Tue, 10 Jul 2007 05:04:52 GMT, the renowned "Michael A. Terrell"
wrote:

lurk wrote:

thanks.....dick smith makes one but is it like the creative electronics
one ?

"Michael A. Terrell" wrote in message
...
lurk wrote:

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks


The schematic is online. It took all of three seconds to find it:
http://bama.edebris.com/manuals/creative/esr

http://members.ozemail.com.au/~bobpar/esrmeter.htm

No, the DSE ESR meter is dugital, and works a lot better on the low
ESR caps in switch mode power supplies. It reads from .01 ohms to 100
ohms on the digital display, and has an automatic zeroing, if the test
leads are clipped together when its turned on. I have, and use the
DSE. I've tried the Creative, but it was almost useless to troubleshoot
the CPU power supplies on computer motherboards

Isn't the DSE one basically an impedance meter though?


Probably. It is microprocessor based, but it works. The fact that
it reads to .01 ohm allows you to test those damn 6.3 VDC electrolytics
used on motherboards. I preferred the Sencore Z-meter I used about 20
years ago, but I simply can't afford one.

Judging by the patent someone referenced, the impedance measurement
should be more than good enough for repair purposes, when carried out
@ 100kHz. The Xc of a 170uF perfect cap is 0.01 ohm.

The Creative is analog, with all the low ESR readings cramped
together at the end of the scale.

What good/bad level are you typically looking for?


Personally, I consider them bad if its more than 10% above the OEM
specifications, but you can't find specs for a lot of the crappy
electrolytics used on motherboards.

The ability to compare all the electrolytics on a bad board give you
some idea of what they were. Usually, the board quits working before
all the caps die. I just make sure the new cap specifications are
better than the lowest cap pulled from the board. Its hard to find GOOD
105 degree low ESR electrolytics in small quantities, and I've used up
all the new caps that I had on hand. I have a pile of fairly new
motherboards with bulging electrolytics that may just go to a local
recycler.

Digikey carries "low impedance" electrolytics in typical values (like
1000uF/6.3V/0.09 ohm/105°C for 28 cents ea. in 10's) but they might be
bigger than the ones used on some mobos. EEU-FC0J102


That's the problem I keep running into. The caps are larger
diameter, and some have wider lead spacing than the cheap crap caps the
OEMs used. There is almost always room for a longer cap.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

lurk wrote:

DSE..... is that dick smith eletronics ? might do the paypal thing.....I'm
impressed with his esr meters.....thanks again Dave


Take a look at Bob Parker's website:
http://members.ozemail.com.au/~bobpar/esrmeter.htm

It looks like DSE's quality has hit rock bottom, but he has allowed
someone else to sell his design.

http://clientes.netvisao.pt/greenpal/evb1.htm is selling it already
built, tested and calibrated for under $100 delivered to Europe, the
United States or Canada.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

On Tue, 10 Jul 2007 14:42:41 GMT, the renowned "Michael A. Terrell"
wrote:

Spehro Pefhany wrote:

On Tue, 10 Jul 2007 05:04:52 GMT, the renowned "Michael A. Terrell"
wrote:

lurk wrote:

thanks.....dick smith makes one but is it like the creative electronics
one ?

"Michael A. Terrell" wrote in message
...
lurk wrote:

Hey speaking about ESR ....I have a Creative Electronics ESR
meter.....and a friend would like to buy one also but it seems like the
company went out of business anybody know about them or their
product... ? or maybe a comparable product ... thanks


The schematic is online. It took all of three seconds to find it:
http://bama.edebris.com/manuals/creative/esr

http://members.ozemail.com.au/~bobpar/esrmeter.htm

No, the DSE ESR meter is dugital, and works a lot better on the low
ESR caps in switch mode power supplies. It reads from .01 ohms to 100
ohms on the digital display, and has an automatic zeroing, if the test
leads are clipped together when its turned on. I have, and use the
DSE. I've tried the Creative, but it was almost useless to troubleshoot
the CPU power supplies on computer motherboards

Isn't the DSE one basically an impedance meter though?


Probably. It is microprocessor based, but it works. The fact that
it reads to .01 ohm allows you to test those damn 6.3 VDC electrolytics
used on motherboards. I preferred the Sencore Z-meter I used about 20
years ago, but I simply can't afford one.

Judging by the patent someone referenced, the impedance measurement
should be more than good enough for repair purposes, when carried out
@ 100kHz. The Xc of a 170uF perfect cap is 0.01 ohm.

The Creative is analog, with all the low ESR readings cramped
together at the end of the scale.

What good/bad level are you typically looking for?


Personally, I consider them bad if its more than 10% above the OEM
specifications, but you can't find specs for a lot of the crappy
electrolytics used on motherboards.

The ability to compare all the electrolytics on a bad board give you
some idea of what they were. Usually, the board quits working before
all the caps die. I just make sure the new cap specifications are
better than the lowest cap pulled from the board. Its hard to find GOOD
105 degree low ESR electrolytics in small quantities, and I've used up
all the new caps that I had on hand. I have a pile of fairly new
motherboards with bulging electrolytics that may just go to a local
recycler.

Digikey carries "low impedance" electrolytics in typical values (like
1000uF/6.3V/0.09 ohm/105°C for 28 cents ea. in 10's) but they might be
bigger than the ones used on some mobos. EEU-FC0J102


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

Spehro Pefhany wrote:

Judging by the patent someone referenced, the impedance
measurement should be more than good enough for repair purposes,
when carried out @ 100kHz. The Xc of a 170uF perfect cap is 0.01
ohm.

Most ESR testers use a 100KHz square wave or a current pulse, so the
capacitor impedance is not relevant.

We can compare the voltage due to the ESR with the triangular ramp
from charging the cap. We can use the bridge circuit to eliminate
the inductive spike.

Voltage due to ESR:

E = I * ESR

Capacitor charging ramp:

I = C * dv / dt

dv = I * dt / C

Set these equal:

ESR = dt / C

From your example:

C = 170e-6
dt = 5e-6

then

ESR = 5e-6 / 170e-6

= 0.0294 ohm

With the above parameters, the capacitive ramp voltage equals the IR
drop at an ESR of 0.03 ohm.

It would be difficult to claim these circuits can measure ESR down
to 0.01 ohm.

You could increase the test frequency or decrease the charging pulse
width to reduce the effect of the charging ramp, but you then run
into problems with the leading and trailing edge inductive spikes.

In a perfect world, the bridge ESR circuit would eliminate the
inductive spike, but it still has implementation problems trying to
measure very low ESR. A two-port measurement with a network analyzer
can follow very low values of ESR, but is impractical for in-circuit
test due to multiple cable and contact problems.

As we ask higher performance from faster circuits, we will
inevitably need to use lower ESR caps.

The current crop of ESR testers probably has reached its limits. We
need a better way to measure ESR for tomorrow's technology.

Regards,

Mike Monett

Mike Monett wrote:

Spehro Pefhany wrote:

Judging by the patent someone referenced,

Sorry Speff, I forgot to ask about the patent you mentioned. Somehow it
doesn't show in my newsreader. Could you post the patent number for
reference?

Thanks,

Best Regards,

Mike Monett

Spehro Pefhany wrote:

4216424

Got it. Thanks,

Regards,

Mike Monett

Mike Monett wrote:

Spehro Pefhany wrote:

4216424

Got it. Thanks,

This seems to be the schematic of the "ESR Meter", which appears in many
places on the web, but the urls in my current archives have expired so I
can't post them for reference.

This is a design from 1980, probably good when the typical ESR was 10 ohms
or more. It no longer applies to current technology.

We need new technology for the second millenium. The first millenium won't
work anymore.

Regards,

Mike Monett

On Tue, 10 Jul 2007 21:07:16 +0000, the renowned Mike Monett
wrote:

Mike Monett wrote:

Spehro Pefhany wrote:

Judging by the patent someone referenced,

Sorry Speff, I forgot to ask about the patent you mentioned. Somehow it
doesn't show in my newsreader. Could you post the patent number for
reference?

Thanks,

Best Regards,

Mike Monett

4216424


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

"Mike Monett" wrote in message
...
Mike Monett wrote:

Spehro Pefhany wrote:

4216424

Got it. Thanks,

This seems to be the schematic of the "ESR Meter", which appears in many
places on the web, but the urls in my current archives have expired so I
can't post them for reference.

This is a design from 1980, probably good when the typical ESR was 10 ohms
or more. It no longer applies to current technology.

We need new technology for the second millenium. The first millenium won't
work anymore.

Regards,

Mike Monett

We need three digits full scale with 1.0mR resolution. Measures any
embedded ESR in capacitors (AC to 1.0MHz), inductors (both AC to 1.0MHz and
DC) or any resistors. That puppy would hunt.

Regards,
Harry

Harry Dellamano a écrit :
"Mike Monett" wrote in message
...
Mike Monett wrote:

Spehro Pefhany wrote:
4216424
Got it. Thanks,
This seems to be the schematic of the "ESR Meter", which appears in many
places on the web, but the urls in my current archives have expired so I
can't post them for reference.

This is a design from 1980, probably good when the typical ESR was 10 ohms
or more. It no longer applies to current technology.

We need new technology for the second millenium. The first millenium won't
work anymore.

Regards,

Mike Monett

We need three digits full scale with 1.0mR resolution. Measures any
embedded ESR in capacitors (AC to 1.0MHz), inductors (both AC to 1.0MHz and
DC) or any resistors. That puppy would hunt.


How much would you or others be ready to pay for this?


--
Thanks,
Fred.

"john jardine" wrote in message
.. .

[...] Clip Teranews comment that's now 2 days out of date.

Had another idea for the original circuit that needed another opamp, so
used 2 of the spare gates in the CD4066 as an oscillator.
Turned out nice. So if anyone needs a quick LC oscillator (below a couple of
meg) a design is here.





--
Posted via a free Usenet account from http://www.teranews.com

"Fred_Bartoli"
r_AndThisToo wrote in
message ...
Harry Dellamano a écrit :
"Mike Monett" wrote in message
...
Mike Monett wrote:

Spehro Pefhany wrote:
4216424
Got it. Thanks,
This seems to be the schematic of the "ESR Meter", which appears in many
places on the web, but the urls in my current archives have expired so I
can't post them for reference.

This is a design from 1980, probably good when the typical ESR was 10
ohms
or more. It no longer applies to current technology.

We need new technology for the second millenium. The first millenium
won't
work anymore.

Regards,

Mike Monett

We need three digits full scale with 1.0mR resolution. Measures any
embedded ESR in capacitors (AC to 1.0MHz), inductors (both AC to 1.0MHz
and DC) or any resistors. That puppy would hunt.


How much would you or others be ready to pay for this?


--
Thanks,
Fred.
Hey Fred,
I'm just a lab rat, wrong nationality to understand financiers but the
above Milli_Ohm Meter with a FLUKE label sounds like $499 USD. With a good
off shore label maybe $299 USD. With the dreaded Boki label.... $49 USD!
Regards,
Harry

"Michael A. Terrell" wrote in message


No, the DSE ESR meter is dugital, and works a lot better on the low
ESR caps in switch mode power supplies. It reads from .01 ohms to 100
ohms on the digital display, and has an automatic zeroing, if the test
leads are clipped together when its turned on.
[snip]

All the leads I've ever seen have a lot more variation than 0.01 ohm if you
breath on them.


--

Reply in group, but if emailing add another
zero, and remove the last word.

Tom Del Rosso wrote:


All the leads I've ever seen have a lot more variation than 0.01 ohm if you
breath on them.


Then don't breathe on them. Now I have to hit you with the
traditional rubber chicken! ;-)


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

On Fri, 13 Jul 2007 19:49:58 GMT, "Michael A. Terrell"
wrote:

Tom Del Rosso wrote:


All the leads I've ever seen have a lot more variation than 0.01 ohm if you
breath on them.


Then don't breathe on them. Now I have to hit you with the
traditional rubber chicken! ;-)

Now what more fowl thing could you do ?

Peter Dettmann

Peter Dettmann wrote:

On Fri, 13 Jul 2007 19:49:58 GMT, "Michael A. Terrell"
wrote:

Tom Del Rosso wrote:


All the leads I've ever seen have a lot more variation than 0.01 ohm if you
breath on them.


Then don't breathe on them. Now I have to hit you with the
traditional rubber chicken! ;-)

Now what more fowl thing could you do ?


Send that irritating AFLAC Duck to bug him? As soon as he finishes
eating that damn Geico Gecko, that is. ;-)


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

"Michael A. Terrell" wrote in message


Send that irritating AFLAC Duck to bug him? As soon as he finishes
eating that damn Geico Gecko, that is. ;-)

I don't even like the Geico Gecko. I found the Dell Dude less irritating.

Anyway, alligator clips do change by several times 0.01 ohm when they move
slightly, so what happens when you clip them together, zero it, then
separate them and clip them to the DUT? Maybe if it was a Fluke it would
come with better clips, but ordinary alligator clips don't seem adaquate.


--

Reply in group, but if emailing add another
zero, and remove the last word.

Tom Del Rosso wrote:
"Michael A. Terrell" wrote in message

Send that irritating AFLAC Duck to bug him? As soon as he finishes
eating that damn Geico Gecko, that is. ;-)

I don't even like the Geico Gecko. I found the Dell Dude less irritating.

Anyway, alligator clips do change by several times 0.01 ohm when they move
slightly, so what happens when you clip them together, zero it, then
separate them and clip them to the DUT? Maybe if it was a Fluke it would
come with better clips, but ordinary alligator clips don't seem adaquate.

I have been known to solder some braid between the handle and the wire
crimp of the alligator clip, when consistent resistance mattered.

-Chuck

Tom Del Rosso wrote:

"Michael A. Terrell" wrote in message


Send that irritating AFLAC Duck to bug him? As soon as he finishes
eating that damn Geico Gecko, that is. ;-)

I don't even like the Geico Gecko. I found the Dell Dude less irritating.

Anyway, alligator clips do change by several times 0.01 ohm when they move
slightly, so what happens when you clip them together, zero it, then
separate them and clip them to the DUT? Maybe if it was a Fluke it would
come with better clips, but ordinary alligator clips don't seem adaquate.


I don't use alligator clips with the ESR meter. I have some of the
old fashion H. H. Smith test probes with very sharp tips. (Think steel
78 phono needles) that are stuck into the tinned lead, (or solder on a
PC board.) then I zero the meter. OTOH I have a set of the insulation
piercing alligator clips made for telco work. One jaw has a bunch of
VERY sharp pins that go though insulation or corrosion to make a low
resistance connection. I don't know where you would buy them. They may
be old Western Union equipment.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

"Michael A. Terrell" wrote in message
...
Tom Del Rosso wrote:

"Michael A. Terrell" wrote in message


Send that irritating AFLAC Duck to bug him? As soon as he finishes
eating that damn Geico Gecko, that is. ;-)

I don't even like the Geico Gecko. I found the Dell Dude less
irritating.

Anyway, alligator clips do change by several times 0.01 ohm when they
move
slightly, so what happens when you clip them together, zero it, then
separate them and clip them to the DUT? Maybe if it was a Fluke it
would
come with better clips, but ordinary alligator clips don't seem
adaquate.


I don't use alligator clips with the ESR meter. I have some of the
old fashion H. H. Smith test probes with very sharp tips. (Think steel
78 phono needles) that are stuck into the tinned lead, (or solder on a
PC board.) then I zero the meter. OTOH I have a set of the insulation
piercing alligator clips made for telco work. One jaw has a bunch of
VERY sharp pins that go though insulation or corrosion to make a low
resistance connection. I don't know where you would buy them. They may
be old Western Union equipment.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Agreed. Croc' clips and normal meter probes are pretty useless for making R
measurements. Even 4 wire Kelvin types I've tried, were pathetic down in
the 10m ohm area. 'Scope probe tips another example, too clunky be much use
with surface mount.
Make my probes from steel sewing needles, epoxied into pen bodies. Ideal for
cutting through oxide layers, or probing tiny SM items. Sufficient strength
to give a little and not snap off like the Tungsten carbide types.







--
Posted via a free Usenet account from http://www.teranews.com