Thoughts on Capacitor Testers
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City: Cape May
State, Province, Country: New Jersey
I would be interested in hearing from members on their thoughts about capacitor tester instrument.
Do you use them
Is an "inline" tester a must
What brand/model do you recommend (any under $50 ?)
Any other comments are welcome.
I have a 42-PT95 chassis that was repaired by a vendor who did a less than stellar job and the radio plays but has problems. They replaced the capacitors, but some of them looks like they may have used NOS parts [they did this in a different radio that had "problems"]. I have new capacitors that I could use and just replace everything again, but would like to try to isolate which capacitor(s) (if that is what is wrong) might be the culprit.
I am new to the game. I have successfully recapped a Philco 48-200, but other radios I have farmed out for repairs. I am looking for some feedback on the usefulness of a capacitor tester.
(This post was last modified: 01-03-2013, 01:11 PM by winkydink.)
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City: Chattanooga
State, Province, Country: TN
I have a capacitive reactance tester on my digital multimeter, but it's of dubious value in testing high voltage electrolytic capacitors as are found in tube radios. It works with a very low DC voltage, so any high voltage leakage won't be detected.
Maybe someone knows of an older type of cap tester that would be better suited. At this point in time though, I'm just going to replace all old caps and any suspected bad newer ones. They aren't terribly expensive.
It's not how bad you mess up, it's how well you can recover.
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City: Merrick, Long Island, NY
I have an ancient Eico bridge that can test caps at rated voltage. If I can't reform an electolytic in a couple of minutes, and have to repeat it the next day, it's toast. Wax caps, no, don't bother, replace them.
Modern digital meters that measure capacitance at a couple of volts are useless for this purpose. May indicate approximate range of nominal value if you are otherwise lost and don't have a schematic.
Pennies. Replace all the caps and old carbon resistors while you are at it. Makes a tremendous difference when you get the set together again.
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City: Sandwick, BC, CA
A lot of people think an ESR tester will tell them whether a cap is good but point in fact they will only tell you which ones are definitely bad. ESR meters are fine in newer solid state electronics where you are only dealing with low voltages of between 6, 12, and 30 VDC, but they give false readings on paper capacitors. A paper cap will often test fine on 9 volts but since it's supposed to test fine at 400-630 volts it really isn't that useful of a test. Eico, Heathkit, B & K, Precision, Solar, RCA, and an number of others made resistance capacitance bridge testers that put high voltage across whatever you are testing, though 400 VDC is usually the maximum. I've made a habit of testing all replacement caps on a bridge before I install them, I've had some NOS surplus caps before that were not really the best, the worst ones are Hunt capacitors.
Regards
Arran
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City: Lexington, KY
While I have an ESR meter I don't use it at all on old radios because of the before-mentioned limitations. I do have an older Heathkit and Jackson capacitor tester that will apply up to 500 volts that makes them useful for testing leakage on the types of caps we use in old radios.
While I always replace all the paper and electrolytic caps when I work on a set I like to check them first for a couple of reasons. One, I have a pretty good stock of quality, but older ceramic & epoxy caps I've picked up at hamfests and the like over the years so I just like to make sure my stock is still good. The second reason is the caps we get today are almost all coming from China and I don't trust their quality control. While none of my older stock has failed a test I have had a couple of the "Chinese specials" test a bit funky.
There are a lot of nice older capacitor testers that will suit our needs, but my personal favorite is a Jackson 650A, mainly because after a rebuild it is pretty accurate, easy to use, and it will test leakage up to 500 volts.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
(This post was last modified: 01-04-2013, 09:07 AM by Eliot Ness.)
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City: Chicago, IL
I generally replace all the old paper and electrolytics caps but I do have this Solar CB-1-60 for testing them. It's handy for mica and ceramic caps too and looks very cool
[Image: http://farm4.staticflickr.com/3509/39045...cd9d_o.jpg]
(This post was last modified: 01-03-2013, 10:02 PM by Bob Andersen.)
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City: Baton Rouge, LA
I have an EICO 950 cap & resistance bridge and use it to check leakage on new & old electrolytics up to 500V. Worth having but be prepared to restore a purchase off eBay. Also have a digital cap tester purchased from AES for about $40.Use it to test caps before installing. I also tried a Heathkit in-circuit cap tester but found it unreliable. Cap testers are not necessary,just a supplement.I replace all paper caps and most high voltage electrolytics w/o testing.
Curt
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City: Merrick, Long Island, NY
I guess we all agree for once. Measure for curiosity, replace for continuity.
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City: Clayton, NC
I use a vintage Jackson 112 Condenser Tester. I like to test all the caps I am installing in a set. The small pain in the thing one sits on factor is outweighed by being sure. Yes, I have found a couple of yellow poly caps that were way out of spec and one that was open.
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City: Hidden Valley, AZ
A simple tool for that task is a vintage Bell System "brownie" or "kick meter".
Originally used for detecting grounds on phone lines, it is an analog d'Arsonval Ohmmeter with a 45-Volt battery supply.
It reads high ohms at that potential, and has a polarity reversing switch that is really handy. Once you get used to what it displays, the results are spot on for me and those pesky old caps.
Dennis
Pacing the cage...
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