Yes it would. It's range is 1 to 22,000 uf. For lower value caps you would need a different tester.

Is uf smaller than microfared rating because some radios have caps .047
.01
.0033
.0039 (use .0033)
.01
.022 microfared thanks

uf (or uF) is the abbreviation for microfarad. The "u" is as close as we can get to the greek letter mu.

If you're on a budget, just find an RLC (Resistance/Inductance/Capacitance) bridge. It will measure coil inductance as well.
Here's one like I use;
http://www.ebay.com/itm/HEATHKIT-IB-528 ... 43af667f53

I need something with audible because I am blind.

Well, the beep doesn't indicate the ESR value nor the capacitor's value. Those are viewed on the lcd display.

The audio tones on the ESR70 are only used as a general indication if the measured ESR value is acceptable for the measured value of capacitance. If the capacitance is well out of tolerance yet the ESR tests OK, the audio tone will be meaningless.

-Mark-

Timmy,

Do you already have a sensitive auditory voltmeter? If so, an older bridge type capacitance meter uses zero volts as the bridge balance indicator. A sensitive digital voltmeter of say 10 megohms per volt, or even less, can be used to bridge the tuning eye or meter indicator to follow the action.

-- Rich

I tried that with a eico 950 b and a audio volt meter and it did not work well. Thanks anyway.

In my humble opinion, these are much much worse than useless.

The way they measure capacitance is not a direct measurement, it's based on the rather thin connection between charging time and capacitance.

If the capacitor is like most of those in an old radio, leaky or dried-out, the capacitance reading can be way, way, way off.

You're much better off with an old true "capacitance bridge". These compare the capacitor against a REAL capacitor and a real series resistor. These bridges lie a whole lot less.

Plus if you have seeing problems, many of the bridges can still be used, you just put some headphones across the "null indicator" posts and adjust the dial for minimum hum or tone ( usually 60Hz or 400Hz on the better bridges). If it has a nice big dial out in the open, you can put braille markings on it or estimate by the angle of the pointer.

With the bridge tester you are talking about can you measure caps in a circuit?

No, but you really can't measure them in a circuit unless they're really BIG capacitors, like 10uF or bigger. In an old radio most of the capacitors have enough resistance across them to make "in circuit" readings very deceptive.

Plus in an old radio there's very little to no need to "measure" capacitors.... All the wax and plastic ones will be bad-- leaky, and almost all the small mica ones will be okay, or too loaded down to be measured. So there's not much point. I always snip out the old wax and plastic tubulars, replace them, then often check the old ones now that they're out of the circuit. Maybe one in a hundred might be okay-- if the radio was kept in a dry attic for the last 50 years. The other 99 are all bad to some extent or another. So a fancy digital cap checker would have been of no use.

As for the bigger electrolytics, you really don't need a cap checker either-- you just turn up the voltage with the variac to 60% or so and watch the voltage across it-- if it comes up nicely to 60% of B+, then it's likely to be okay. If the speaker doesn't hunm, the cap is okay. And vice-versa. A digital cap checker doesn't really help all that much here either. It might tell you the cap is 14uF instead of 20, and that the ESR is 10 ohms, but the speaker hum tells you the same info, more accurately, and for free. The bottom line is: does the B+ go and stay up, and is the B+ hum free enough?

You know, the bottom line here is simply to replace all wax/paper/Bumble Bee/plastic/Electrolytic caps 40+ years old.

Given the low cost for replacements, why mess around with measuring at all?

I almost never need to use my bridge, except when needing to know the inductance of a coil, which is seldom.

Hello Ancient_Hacker,
“Much much worse than useless”???? Having owned an Atlas ESR70 for two years, I have a different take on ownership. I have measured all manner of caps from 1ufd up, and compared it against a Leader LCR meter, Sencore “Z-Meter”, and Wavetek CR-50, and found the accuracy to be more that satisfactory - from RF applications to simple pwr sply testing. While one has to be “careful” interpreting the ESR measurement, especially for 60 Hz and 120 Hz filter applications, I find the ESR70 to be very convenient and easy to use. I also like its low-ohms capability. I checked its accuracy against standard capacitors including my GR 1412-BC Decade capacitor. I have an EE background that includes calibration and metrology, and have no qualms recommending an ESR70 to the folks on this forum, as long as they can understand and use the ESR data. I have been so pleased with the operation, versatility/portability, and ease of use of the ESR70 that I recently purchased the matching Atlas LCR40 automatic passive component analyser. Both of them have a place on my test bench, and I find that my “Z-Meter” is “gathering dust” for lack of use….
Dave – WA6VVL

Different tools = different tasks. The ESR70 is excellent at what it does, and ESR testing for electrolytics is an important measurement perimeter to test. It's application applies much more to the e-caps found in solid state equipment rather than with tube gear. When you have a piece of solid state gear that might contain dozens or even hundreds of e-caps, the ESR test is very effective at picking out the bad boys where it's impractical to replace every single e-cap. With old tube gear we generally need to replace the paper and likely the few e-caps contained within anyways as a matter of course or common sense, right? So why is there all this fuss over intricate and/or expensive cap testers or bridges for examining the capacitors used in that type of equipment? To yank them out, test and confirm that 99% of them are indeed leaky or well out of tolerance as a feel-good measure, and then replace them?

-Mark-

Yes, for fixing old radios. For the reasons stated.

If instead you are: (1) Designing 400 Hz, 80dB deep analog notch filters or (2) For some unfathomable reason, testing capacitors in a PC power supply, or (3) Making your own ICBM inertial guidance system with analog integrators, then, and only then. that meter may be more useful.

But for fixing up old radios, that kind of meter is much, much, much worse than nothing at all. First, it cost you money. Secondly, it is guaranteed to give you the wrong answer, Thirdly, you really don't care what the capacitance is of the wax capacitors, they really can't lose or gain capacitance. Fourthlly, what you DO want to know, their leakage at 300 volts, the meter can't do. Fifffffthly, where it *might* be useful, in measuring the ESR of the electrolytics, it misleads you again, because the meter is probably designed and optimized and most accurate for measuring milliohms of ESR, not ohms, and it can't even measure that under operating voltage and with the cap all formed up.. Sixthly, if I really wanted to know the exact capacitance of a capacitor, Id want to test it under the right Dc voltage, and at the frequency of interest. Yes, that matters, but those little handheld meters can't do either of those things.

So, it gives you the wrong answers under the wrong test conditions to questions you'd never want to ask and on capacitors that you know are bad and that can never vary anyway, and the meter takes you away from useful tasks and it cost you money. Been there, done that, several times, and it took me several years to realize the foolishness of putting a 70 yr old dirty wax cap onto a $4,000 meter and staring at 4 significant digits of capacitance, ESR and power factor.

For the record, I too foolishly bought a Heathkit digital cap meter at an estate sale, and along with a nice HP 4230? digital cap meter, I occassionally use them to verify that a cap labelled "100" is really 10pF, not 100pF, as is sometimes the case.

Hi,

As a standard rule I only exchange capacitors at critical spots in old sets.
The rest is checked in the circuit by an ESR-Micro V4 from Russia.
This meter (0.02 to 60,000 microF) does a better job than my Fluke 87
The Fluke also takes the parallel resistance in account and often gives too high a reading.
In doubt I unsolder one side of the capacitor or put it completely in a Marconi LCR bridge.

In principle I try to keep the radio as original as possible ,at the inside and exterior.

As a matter of fact also the Mona Lisa is not repainted with modern paint

Best Regards Jard N.

I'm sure they Mona Lisa would look just as good as the original as a modern paint-by-number.

But I think we may be getting off track here in our enthusiasm to beat the ESR dead horse.

Timmy is blind. (Which makes him a braver man than I.) As I understand it he's looking for a audible capacitance meter. Perhaps someone has seen one. Unfortunately I haven't. I have to wonder if there wouldn't be easier to modify a normal capacitance meter to give it a voice, since they seem to be rare.

If he can use a computer and has one near his lab, He may be able to get away with a multimeter with a computer interface: Something like this: It doesn't do ESR, and won't test at working voltage, but if the goal is just to measure capacitance.

http://uk.farnell.com/tenma/72-7732/mul ... dp/1563719

(I used Farnell's site since the MCM site is down at the moment. - No affiliation, MCM is just local to me. This should be available via MCM as well. )

Edit: MCM Link: http://www.mcmelectronics.com/product/72-7730 Not quite the same, different range, but still USB. I guess the 7732 wasn't available at MCM.

There's also self built projects like this:

http://embedded-lab.com/blog/?p=4400

Again, no ESR, nor working voltage test, and I've not built it, it was just one I found. It is microcontroller based, so I would think it could be relatively easily adapted to send its measurements to a speech synthesizer instead of the LCD display.

Frankly, if I'm measuring capacitance, and I have to worry about ESR, I just presume its bad, and replace. Yes, I probably do replace more capacitors than necessary.

David

What exactly are, "critical spots"? Do they include filter Electrolytics?


As a matter of fact The Mona Lisa only has one purpose...To be viewed.

Quite different from an appliance that has an electronic function, and parts that wear out over time, serving that objective.