I have a whole box of mica capacitors although were orginally color-coded are difficult to determine. Are there multimeters that can measure capacitance that low?

A popular auction site has a Philips up for grabs as we speak:

http://cgi.ebay.com/Philips-ECG-CX-920A-Digital-Capacitance-Meter-w-Leads_W0QQitemZ270213089980QQihZ017QQcategoryZ73160QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

:I have a whole box of mica capacitors although were orginally color-coded are difficult to determine. Are there multimeters that can measure capacitance that low?

That meter is available under many names. Antique Electronics Supply has the same one as S-Z150 For $39.95. I have the exact same meter as this under the Mastech name, I got it from MCM Electronics for about that much a couple of years ago. It works very well. If a capacitor is leaky the reading is different under different scales. I mean if you use the 10uF scale to read a 5uF cap, then switch to the 100uF scale, the reading should be near 5uF for both. But may show up as 8 on one scale and 25 on the other. I like this meter and I would recommend it. You might want to get longer leads since it comes with ones that are only 6" long. Only draw back is the cap has to have one lead lifted from the circuit to be accurate. Hope this helps!

Brian,
I have a B&K 388B from a few years ago that does the job, but only goes to 40uf on the scale knob. Keep in mind that it is a low voltage test, and that may not reveal other defects in the caps. I made a set of 18" test leads from very small, very flexible test lead wire, but if closely spaced during tests, the leads will contribute a few picofarads in parallel with DUT.

marv

:I have a whole box of mica capacitors although were orginally color-coded are difficult to determine. Are there multimeters that can measure capacitance that low?

Here's one that will go down to 1pf up to 200uf
...but it will also measure inductance.
.. I think from 10uh to 20H

http://cgi.ebay.com/LCR-RCL-INDUCTANCE-CAPACITANCE-RESISTANCE-METER_W0QQitemZ280202845624QQihZ018QQcategoryZ4678QQrdZ1QQssPageNameZWD2VQQcmdZViewItem?_trksid=p1638.m122

Peter,
Dave seems happy with his cheapie, but the ebay item you noted @$9.95 for a DMM/LCR from China is a bit suspicious. No doubt Chinese QC is improving, but if it fails, where do you get it repaired or repair parts? They're still using lead based paint on kid's toys, recently metal fragments were found in kid's lollipops, fake prescription drugs are every day occurrences, chemical laced pet food. Where will it end, and when will we greedy Americans stop buying their inferior cheap crap from soup to nuts.

marv

:Here's one that will go down to 1pf up to 200uf
:...but it will also measure inductance.
:.. I think from 10uh to 20H
:
:http://cgi.ebay.com/LCR-RCL-INDUCTANCE-CAPACITANCE-RESISTANCE-METER_W0QQitemZ280202845624QQihZ018QQcategoryZ4678QQrdZ1QQssPageNameZWD2VQQcmdZViewItem?_trksid=p1638.m122

Marv:
I was just trying to point out that he could, for about the same money, include inductance on one meter.

I don't know if it's a certainty that things from China are no good though.

Metal fragments in lollipops?
... humm... sounds like a reasonably creative attempt at population control...no?
...lol
Peter

:Peter,
:Dave seems happy with his cheapie, but the ebay item you noted @$9.95 for a DMM/LCR from China is a bit suspicious. No doubt Chinese QC is improving, but if it fails, where do you get it repaired or repair parts? They're still using lead based paint on kid's toys, recently metal fragments were found in kid's lollipops, fake prescription drugs are every day occurrences, chemical laced pet food. Where will it end, and when will we greedy Americans stop buying their inferior cheap crap from soup to nuts.
:
:marv
:
::Here's one that will go down to 1pf up to 200uf
::...but it will also measure inductance.
::.. I think from 10uh to 20H
::
::http://cgi.ebay.com/LCR-RCL-INDUCTANCE-CAPACITANCE-RESISTANCE-METER_W0QQitemZ280202845624QQihZ018QQcategoryZ4678QQrdZ1QQssPageNameZWD2VQQcmdZViewItem?_trksid=p1638.m122

Yea Peter population control, but in our day care centers no China.

marv

:Marv:
:I was just trying to point out that he could, for about the same money, include inductance on one meter.
:
:I don't know if it's a certainty that things from China are no good though.
:
:Metal fragments in lollipops?
:... humm... sounds like a reasonably creative attempt at population control...no?
:...lol
:Peter
:
::Peter,
::Dave seems happy with his cheapie, but the ebay item you noted @$9.95 for a DMM/LCR from China is a bit suspicious. No doubt Chinese QC is improving, but if it fails, where do you get it repaired or repair parts? They're still using lead based paint on kid's toys, recently metal fragments were found in kid's lollipops, fake prescription drugs are every day occurrences, chemical laced pet food. Where will it end, and when will we greedy Americans stop buying their inferior cheap crap from soup to nuts.
::
::marv
::
:::Here's one that will go down to 1pf up to 200uf
:::...but it will also measure inductance.
:::.. I think from 10uh to 20H
:::
:::http://cgi.ebay.com/LCR-RCL-INDUCTANCE-CAPACITANCE-RESISTANCE-METER_W0QQitemZ280202845624QQihZ018QQcategoryZ4678QQrdZ1QQssPageNameZWD2VQQcmdZViewItem?_trksid=p1638.m122

I purchased an LCR multimeter from http://stores.ebay.com/Broadway-Electronics. It covers a wide range from 1pf to 200 mf. It's a cheap import, but surprisingly, it's very accurate.

Dave, is this the L/C meter you have:
http://cgi.ebay.com/Digital-LCR-MultiMeter-Inductance-Meter-Tester-NEW-AR_W0QQitemZ160210987380QQihZ006QQcategoryZ25421QQtcZphotoQQcmdZViewItemQQ_trksidZp1713.m153.l1262

The way I read it, the lowest capacitance scale has a resolution of 1pF, but the accuracy is supposedly = +-(2.5% + 20pF). That might not hack it for measuring a small-value cap.

Here is info on my L/C meter, $100 in kit form: http://www.aade.com/lcmeter.htm The precision and accuracy is very high - sufficient for analyzing many RF resonant circuits.
Doug

:I purchased an LCR multimeter from http://stores.ebay.com/Broadway-Electronics. It covers a wide range from 1pf to 200 mf. It's a cheap import, but surprisingly, it's very accurate.
:

:I have a whole box of mica capacitors although were orginally color-coded are difficult to determine. Are there multimeters that can measure capacitance that low?

i have the philips from aes and it does work well but the leads are not the greatest,they tend to break inside the insulation after use so if you get erratic readings with one, tug on each lead if one starts to strech, the wire is broke inside and needs to be resoldered.butch

Brian, I was just thinking. Depending upon how big that box of caps is, they may not justify the cost of buying an L/C meter with really decent precison and accuracy for sizing small-value caps. And small mica caps are often used in resonant RF circuits where the cap's value is pretty important.

Silver mica caps typically cost around 50 cents each, and the original ones in old radios often are OK.
Doug

:I have a whole box of mica capacitors although were orginally color-coded are difficult to determine. Are there multimeters that can measure capacitance that low?

Brian,
Send them to me, I'll test them and re-mark them with color dots for 10% of the Booty.

marv

:I have a whole box of mica capacitors although were orginally color-coded are difficult to determine. Are there multimeters that can measure capacitance that low?

Brian, Marv's offer sounds pretty good. You will not be able to accomplish what you want with those $10-30 testers that I've seen described. They're just not accurate and precise enough for sizing small mica caps.
Doug

:Brian,
:Send them to me, I'll test them and re-mark them with color dots for 10% of the Booty.
:
:marv
:
::I have a whole box of mica capacitors although were orginally color-coded are difficult to determine. Are there multimeters that can measure capacitance that low?

Doug: What is it exactly about these specs on that first meter that precludes accurate measurement of say a 10pf or 50 pf cap as an example?

Features:
*0.1 pF to 20mF, (20,000 uF) 9 Ranges
*0.5% Basic Accuracy
*3-1/2 Digit LCD, 0.55" H

:Brian, Marv's offer sounds pretty good. You will not be able to accomplish what you want with those $10-30 testers that I've seen described. They're just not accurate and precise enough for sizing small mica caps.
:Doug

Peter: No, sorry, I was commenting on the $26 meter mentioned by Dave Sica: http://cgi.ebay.com/Digital-LCR-MultiMeter-Inductance-Meter-Tester-NEW-AR_W0QQitemZ160210987380QQihZ006QQcategoryZ25421QQtcZphotoQQcmdZViewItemQQ_trksidZp1713.m153.l1262

The first meter is OK, based on what the description says - 0.1pF, 0.5% accuracy. However, I think sometimes meter accuracy is specified as a percent of full scale on whatever range you're on, so I'm not completely sure. But the Philips brand is respected.
Doug

:Doug: What is it exactly about these specs on that first meter that precludes accurate measurement of say a 10pf or 50 pf cap as an example?
:
:Features:
:*0.1 pF to 20mF, (20,000 uF) 9 Ranges
:*0.5% Basic Accuracy
:*3-1/2 Digit LCD, 0.55" H
:
:
::Brian, Marv's offer sounds pretty good. You will not be able to accomplish what you want with those $10-30 testers that I've seen described. They're just not accurate and precise enough for sizing small mica caps.
::Doug
:

Peter,
Am I missing something here? How do you display 0.5% measurement of 0.1pf on a 3 1/2 digit meter display. Thats 5 to -16th pf.

marv

:Doug: What is it exactly about these specs on that first meter that precludes accurate measurement of say a 10pf or 50 pf cap as an example?
:
:Features:
:*0.1 pF to 20mF, (20,000 uF) 9 Ranges
:*0.5% Basic Accuracy
:*3-1/2 Digit LCD, 0.55" H
:
:
::Brian, Marv's offer sounds pretty good. You will not be able to accomplish what you want with those $10-30 testers that I've seen described. They're just not accurate and precise enough for sizing small mica caps.
::Doug
:

Marv:
Why are you asking me? I don't ''rep'' the company...lol

but I'll take a guess here...
.05% is the anticipated maximum error.

So I don't know how the display would show the correct value of .1pf... unless it was .100pf... and let's see... and maybe if it was .05% low... it might read .999?

:Peter,
:Am I missing something here? How do you display 0.5% measurement of 0.1pf on a 3 1/2 digit meter display. Thats 5 to -16th pf.
:
:marv
:
:
::Doug: What is it exactly about these specs on that first meter that precludes accurate measurement of say a 10pf or 50 pf cap as an example?
::
::Features:
::*0.1 pF to 20mF, (20,000 uF) 9 Ranges
::*0.5% Basic Accuracy
::*3-1/2 Digit LCD, 0.55" H
::
::
:::Brian, Marv's offer sounds pretty good. You will not be able to accomplish what you want with those $10-30 testers that I've seen described. They're just not accurate and precise enough for sizing small mica caps.
:::Doug
::

-- CORRECTION ----
Marv:
Why are you asking me? I don't ''rep'' the company...lol

but I'll take a guess here...
.05% is the anticipated maximum error.

So I don't know how the display would show the correct value of .1pf... unless it was .100pf... and let's see... and maybe if it was .05% low... it might read .099?