Concerning vintage electronics from the 20s to the 50s it is a waste of time to test the old paper and electrolytic caps, but there is one application for an ESR meter: testing the NEW parts that are about to be installed. Considering where they are made today, I think it is essential to at least do a spot check of components when they are received from a vendor. Of course, caps below .47 will not read, so a power supply and micro-ammeter are needed to test those.

I'm pretty sure the Dick Smith tested at 100kHz.

ESR meters, selenium rectifiers, and electrolytics in series.

RRM

Both the Anatek Blue (new Dick Smith, but its been around a while) and Peak Atlas test at the "industry standard" 100 kHz. The Blue was my runner up choice over the Peak, but the non-polarized connection and protection circuitry really sold me on the Peak and its not really that much more expensive. A lot of people have damaged their Blue meters by connecting to charged caps, its a very easy thing to do on a board filled with caps and you forget to discharge them. But if used properly the Blue will get the job done.

-Mark-

Even 30 years or longer ago when Creative Electronics came out with what may have been the first affordable ESR meter, the unit ran at 100KHz which was changed to 50KHz when they were having problems finding IC's that would work in their circuit at the higher frequency. I don't understand why any manufacturer since that time would have thought it was OK to run the test at a substantially lower frequency.

Perhaps someone with a spectrum analyzer could check that 2-kHz pulse train from the Dick Smith ESR tester and tell us what the frequency content is.

The Pulse Repetition Frequency (PRF) may be 2-kHz, but the frequency content will extend well above that. It is the pulse width that is important here, not so much the PRF.

The "Dick Smith" ESR meter is actually from Bob Parker in Australia. He licensed it out to Dick Smith Electronics until they went under. Anatek and others are now liceneced for the meter. Depending on who has it, there as some slight differences, from case (Blue for Anatek, black with a red label for a version in Portugal), to the name ("Blue ESR Meter" for Anatek, "EVB" meter for the Portugal version, etc..) to other things (The Portugal version seems to have the diode mod built in, as it handles 400V protection).

Regarding the pulse, Anatek's comparison page states for it's method:



In Bob's kit manual, it states:



BTW, fault codes to help the builders, were also in the "Dick Smith" version.

The test frequency has to be high enough that the capacitive reactance is substantially lower than the ESR, since the meter is displaying the sum.

Exactly. The distinction between ESR—Equivalent Series Resistance—and capacitive reactance can’t be pointed out too often, if the many discussions here of condenser testing are any indication. A standard impedance bridge will not permit the testing (as opposed to measurement) of electrolytic condensers in-circuit, which is the raison d’être of an ESR meter.

An ESR meter is in fact very useful in trouble-shooting vintage radios—vintage transistor radios. A transistor radio can be up to 58 years old now, older than a great many tube sets when they were being collected as “antiques”. And an ESR meter is virtually essential for trouble-shooting modern electronic equipment. It will save a vast amount of time.

The ideal testing frequency appears to be in the vicinity of 100 kilocycles. My own ESR tester is a home-made adapter, employing a transistor Hartley oscillator at 140 kilocycles, which is used in conjunction with a high-frequency volt-meter, usually a portable Hewlett-Packard 427A. In many years of use it has never failed to identify the bad electrolytic condensers in solid-state equipment.

On this page—

http://www.flippers.com/esrkthnt.html

—the Dick Smith ESR meter is stated to employ a 2-kilocycle train of 10-microsecond pulses at an open-circuit amplitude of 600 millivolts. This signal, shown in the picture above, is similar to the output of a blocking oscillator signal injector (albeit lower in voltage). As Ed insightfully pointed out above, because of the harmonic content of the pulses, the meter works similarly to those employing conventional waveforms at 100 kilocycles.

On this page—

http://www.anatekcorp.com/esr_compare.htm

—it can be seen that the Anatek Blue ESR meter carries over the pulse concept, and the pulse train is described as having an “effective frequency” of 100 kilocycles. There’s no mystery here, after all. Pulse waveforms like this have long been used in this way, often when it was desired that a low-cost circuit produce a signal with both an audio tone and a “radio frequency” component. I recall a 1960s White’s T-R metal detector circuit that employed a blocking oscillator in this manner. Signal injector probes have been discussed here many times.

The testing frequency is also an important factor in measuring capacitance and inductance. Small condensers and coils intended for RF circuits are best measured in the vicinity of the frequencies at which they will be used. My bench LC meter was made by Tesla in Czechoslovakia, and it works by placing the condenser or coil to be measured across a standard inductance or capacitance, respectively (different standards for the various ranges). By adjusting the measurement dial, the frequency of a VFO is swept. An amplifier and detector indicate the resonance peak on a meter. The reading is taken from the dial when the peak is located. This method of measurement insures that components are measured at appropriate frequencies. And in fact, differences in the height and sharpness of the resonance peak indicate Q, although in a relative, un-calibrated, manner. A proper Q-meter will do all of this, and indicate a value for Q as well.

HI ALL:

I AGREE WITH JOHNNYSAN. I HAVE OWNED MY EDS 88A SINCE 2004.NOW PRICED AT $200.00.
I SERVICED ALL KINDS OF ELECTRONICS AND IT HAS BEEN A REAL TIME SAVER WITH IN CIRCUIT TESTING USING A TWEEZER PROBE.YOU DO NOT HAVE TO OBSERVE POLARITY OF THE PROBE AS IT USES A AC VOLTAGE. AN ELECTROLYTIC CAN CHECK GOOD FOR CAPACITY AND LEAKAGE ON A LC METER BUT THE REAL PROBLEM IS THE ESR. A CAP MAY NOT SHOW BULGING BUT STILL HAVE HIGH ESR. I HAVE HAD TO CHANGE THE BATTERY A COUPLE OF TIMES BUT IT WAS USED EVERY DAY.IT ALSO HAS AUTOMATIC SHUT OFF TO PRESERVE BATTERY USAGE.IN SWITCHING POWER SUPPLIES I MOSTLY FIND THE SMALL CAPACITY FEEDBACK CAP THE PROBLEM SO THAT IS ALWAYS CHANGED PERIOD.SOME OF THE COMPUTER POWER SUPPLIES ARE REALLY PACKED TIGHT.NOT ALWAYS AN EASY QUICK REPAIR.THE EDS ALSO HAS A TABLE ON THE FRONT.I CANNOT SERVICE WITH OUT IT TODAY.YOU CAN FIND IT ON THE INTERNET.PLEASE TAKE A LOOK.

BEST REGARDS
WALTER-W2WIQ

Thanks to all who responded. I have chosen the blue Anatek because it is less than some of the others and does the same job. I'm sure I would have been just as happy with the Peak or the EDS, just wouldn't have lunch money for the rest of the week
Now on to learning more on these late model SMPS.

I've been lusting after a HP 4800A vector impedance meter http://www.ebay.com/sch/i.html?_nkw=hp+4800a+meter for measuring ESR See the HP Journal article on it: http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1967-01.pdf

I may have to homebrew one. Center-zero meters are getting hard to find, though.

Best regards,
-Steve

I didn't get scared away. I was able to wade thru the "extreme" reccomendations. I just wanted a simple way to weed out the seemingly plentiful rash of bad electrolytics out there in the ever popular TV's and such. I luckily found a replacement PS board for my LCD tv, but maybe with an ESR meter I could have pinpointed a bad cap and not had to wait as long searching for a used pull off ebag. I didn't want to trial and error cobble something together or use a complex set-up of older scope and bridges when there is a reasonably priced unit out there already. I guess some just believe it's too simple to be good.

I second the motion regarding a current probe. One point (OK, two) - be sure to get one that can handle fast transients and moderately high peak currents if you're seriously considering working on modern switchers. Buy the "best that you can afford."

MBIRD97X

I AGREE WITH WHAT YOU DESIRE. I SILL RECOMEND THE EDS88A IF YOU CAN AFFORD THE $200.00.VERY SIMPLE & QUICK CHECKS. I'VE USED IT MOSTLY IN TV,MONITORS AND SWITCHING SUPPLIES FOR THE PAST 9 YEARS.
YOU CAN DOWNLOAD THE INSTRUCTION MANUAL AT THIS LINK UNDER CALIBRATION INSTRUCTIO DOWN THE PAGE YOU WILL FIND THE LINK.IT IS A MICROSOFT WORD DOCUMENT.WORTH READING.

http://www.eds-inc.com/eds88.html

GOOD LUCK.

WALTER-W2WIQ