Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => AmpTools/Tech Tips => Topic started by: p2pAmps on January 05, 2017, 08:59:17 am

Title: Capacitor testers
Post by: p2pAmps on January 05, 2017, 08:59:17 am
Guys,

I would like some input on capacitor testers.  Right now I have a Atlas ESR tester that works nice on caps 1uF or higher for my purposes.  I want to test for leaking coupling caps.  I know about the Sencore stuff but it is pretty expensive. 

What are ya'll using or are you testing in the amp itself under full voltages?

~mike
Title: Re: Capacitor testers
Post by: shooter on January 05, 2017, 09:33:44 am
Quote
in the amp itself under full voltages?
I use my fluke 87 for basic testing, but don't have anything but the real thing for dynamic testing.
Title: Re: Capacitor testers
Post by: sluckey on January 05, 2017, 09:52:20 am
I had access to this cap analyzer for about 30 years. I got bored one day and turned it on!  :icon_biggrin:

http://www.ebay.com/itm/SPRAGUE-TEL-OHMIKE-TO-6-A-CAPACITOR-ANALYZER-TESTED-WORKING-/282310788105?hash=item41bb08c409:g:X9QAAOSw5cNYaUbK (http://www.ebay.com/itm/SPRAGUE-TEL-OHMIKE-TO-6-A-CAPACITOR-ANALYZER-TESTED-WORKING-/282310788105?hash=item41bb08c409:g:X9QAAOSw5cNYaUbK)

I use a dmm to check for leakage in circuit. Usually have to disconnect one end of the suspect cap.
Title: Re: Capacitor testers
Post by: p2pAmps on January 05, 2017, 10:06:51 am
I had access to this cap analyzer for about 30 years. I got bored one day and turned it on!  :icon_biggrin:

http://www.ebay.com/itm/SPRAGUE-TEL-OHMIKE-TO-6-A-CAPACITOR-ANALYZER-TESTED-WORKING-/282310788105?hash=item41bb08c409:g:X9QAAOSw5cNYaUbK (http://www.ebay.com/itm/SPRAGUE-TEL-OHMIKE-TO-6-A-CAPACITOR-ANALYZER-TESTED-WORKING-/282310788105?hash=item41bb08c409:g:X9QAAOSw5cNYaUbK)

I use a dmm to check for leakage in circuit. Usually have to disconnect one end of the suspect cap.

That's funny as I am watching that one Steve...
The Sencore LC102 is another but pretty big price tag goes along with that one

I've been using my Fluke 117 like you and lifting one side as well.  Just wondering if I am really getting the whole story or is that good enough and full proof...
Title: Re: Capacitor testers
Post by: sluckey on January 05, 2017, 10:28:00 am
I've made out just fine for over 45 years with just a multimeter. I do like having an analog as well as my dmm. And an analog VTVM has advantages as well. Use the dmm to check for leaky coupling caps. Use the VTVM ohm function to check electrolytic leakage or shorts.

Oh, one other thing... I wont spend $10 worth of time obsessing over a $1 cap. If I still have suspicions about a cap after the simple meter checks, I'll resort to the substitution method.

Title: Re: Capacitor testers
Post by: p2pAmps on January 05, 2017, 10:45:21 am
I've made out just fine for over 45 years with just a multimeter. I do like having an analog as well as my dmm. And an analog VTVM has advantages as well. Use the dmm to check for leaky coupling caps. Use the VTVM ohm function to check electrolytic leakage or shorts.

Oh, one other thing... I wont spend $10 worth of time obsessing over a $1 cap. If I still have suspicions about a cap after the simple meter checks, I'll resort to the substitution method.

I'm with you on all accounts Steve.  Lately I've had a run of late 50s tweeds hit the shop and these guys obsess over those old Astrons and such. 
Title: Re: Capacitor testers
Post by: jjasilli on January 05, 2017, 08:23:56 pm
FWIW I use a vintage Eico 950B Comparator. It can put 500V on a cap.  Currently they go for about $50 on eBay.
Title: Re: Capacitor testers
Post by: John on January 11, 2017, 01:31:44 pm
FWIW I use a vintage Eico 950B Comparator. It can put 500V on a cap.  Currently they go for about $50 on eBay.


I've got a heathkit C-3, probably very similar. Also will put high voltage on the cap. Don't lick it while it's on!
Title: Re: Capacitor testers
Post by: p2pAmps on January 11, 2017, 07:04:23 pm
I picked up a very mint Sprague Tel-Ohmike TO-6A today.  I figured what the hell, it will be fun and who know, might just catch a bad cab or two...

(https://static1.squarespace.com/static/56fbe87462cd94ff6ec9d02c/56fe7d702fe131ac8a5ed90e/5876d57df5e231f7a6cb7ff9/1484182911096/IMG_7833.JPG.jpeg?format=2500w)
Title: Re: Capacitor testers
Post by: whoops on January 11, 2017, 10:50:23 pm
I picked up a very mint Sprague Tel-Ohmike TO-6A today.  I figured what the hell, it will be fun and who know, might just catch a bad cab or two..

You can use that to reform NOS Electrolytic caps.

If you are using Electrolytic caps that were in storage for 3-5 years, better to reform them before using.

Storage time can be at the warehouse, store, or at your workshop. Basically the time since they've left the factory to the moment  you solder them up.
Title: Re: Capacitor testers
Post by: p2pAmps on January 12, 2017, 09:32:53 am
I picked up a very mint Sprague Tel-Ohmike TO-6A today.  I figured what the hell, it will be fun and who know, might just catch a bad cab or two..

You use that to reform NOS Electrolytic caps.

If you are using Electrolytic caps that were in storage for 3-5 years, better to reform them before using.

Storage time can be at the warehouse, store, or at your workshop. Basically the time since they've left the factory to the moment  you solder them up.

Yes that's right.  Pretty cool box really and so far dang accurate too when I cross test a few things.  Looking forward to spending more time with her when things slow up a tad.
Title: Re: Capacitor testers
Post by: jjasilli on January 12, 2017, 01:04:08 pm
I picked up a very mint Sprague Tel-Ohmike TO-6A today.


It's gorgeous!  :thumbsup:
Title: Re: Capacitor testers
Post by: DummyLoad on February 07, 2017, 01:54:11 am
sencore LC53. 


--pete
Title: Re: Capacitor testers
Post by: p2pAmps on February 07, 2017, 09:48:39 am
Yeah, love those Sencore LC103 but a little rich for this poor boy
Title: Re: Capacitor testers
Post by: whoops on February 07, 2017, 10:09:47 am
Hi,
just to let you know I bought this unit some weeks ago just to try it out as it was really cheap.

http://www.ebay.com/itm/Portable-MK328-LCR-ESR-Tester-transistor-inductance-capacitance-resistance-meter-/171927184554?hash=item2807a8a4aa:g:MdoAAOSwk0pVgETb (http://www.ebay.com/itm/Portable-MK328-LCR-ESR-Tester-transistor-inductance-capacitance-resistance-meter-/171927184554?hash=item2807a8a4aa:g:MdoAAOSwk0pVgETb)

After using it I must tell you it works great.

On the Capacitor side it measures, Capacitance, ESR and voltage loss after a pulse. The readings I got were spot on with other meters I have.


It also measures transistors, inductors, resistors, Leds.

It's a great a useful overall measuring tool. Highly recommended