Test Equipment Webpage - Page 1
Forum section: electronics / testgear

author: wn1fju
author_rank: Frequent Contributor
timestamp: August 23, 2014, 12:18:33 pm
content: For those with interest and/or patience, here's a collection of 1970-1990's test equipment:http://emperoroftestequipment.weebly.com/What started out as a simple way to catalog my collection so I don't buy things I already have, as well as having a record of my repair notes, has evolved into a semi-humorous commentary.The page is long (particularly the set of HP equipment), but maybe people fixing their own vintage pieces can learn from my mistakes and triumphs.Enjoy!

author: argg
author_rank: Contributor
timestamp: August 23, 2014, 01:12:46 pm
content: excellent webpage with a wealth of informationThanks!

author: retiredcaps
author_rank: Super Contributor
timestamp: August 23, 2014, 09:09:58 pm
content: Quote from: wn1fju on August 23, 2014, 12:18:33 pmExcellent webpage with good info. I plan to read every entry.PS. Thanks for making it ad-free as well.

author: radhaz
author_rank: Regular Contributor
timestamp: August 24, 2014, 03:54:22 am
content: Excellent site. I bought a Power Designs 340 off of Ebay that was declared as working. A channel would power up to 18 VDC no matter the pot setting, and later failed completely. The service manual provided excellent trouble shooting tips, and I found and replaced the shorted output transistors. I love the old boat anchor gear!

author: Electro Fan
author_rank: Super Contributor
timestamp: August 24, 2014, 04:13:18 am
content: Thanks for sharing! Both informative and entertaining. Good history, practical experience, and insights.

author: calmtron
author_rank: Regular Contributor
timestamp: August 24, 2014, 07:39:36 am
content: Really nice, read it straight through, made my morning. Glad I'm not the only one crazy enough to repair old measurement gear just for the sake of fixing it, without really having a use for it

author: Bryan
author_rank: Frequent Contributor
timestamp: August 24, 2014, 11:06:32 am
content: Wow, love it. Good work

author: TerraHertz
author_rank: Super Contributor
timestamp: August 24, 2014, 11:16:26 am
content: That was a fun read!Only, you nearly gave me a heart attack when I read this:"HP 3586B: Selective level meter, 200 Hz to 32.5 MHz. ...Boy was this a pain in the butt. The NiCd batteries had leaked and caused ..."I have a HP 3586B sitting in a rack. Reading that I immediately thought "NiCad? What NiCad? I didn't know there was a NiCad in that. Ooohhhh crap."It hasn't been turned on in a long while.Expecting a big disappointment I pulled it out and opened it up. Phew! The battery had already been removed by someone. Probably by the prior owner, since the repair of the small amount of battery leakage damage to the A80 board isn't in my style. I always coat the cleaned-up area in grease, since it stops further corrosion of the traces and leads, which seem to be infused with H+ ions or something after a NiCad accident.

author: kikook
author_rank: Contributor
timestamp: August 24, 2014, 11:19:44 am
content: I like this page !A BIG Thanks !

author: SeanB
author_rank: Super Contributor
timestamp: August 24, 2014, 11:54:03 am
content: Quote from: TerraHertz on August 24, 2014, 11:16:26 amWash it with vinegar and then the alkali will be neutralised. Then you can rinse with water and leave to soak for a while to get it back to neutral. If you can get it use some pH7 buffer solution to get the last ions out.

author: TerraHertz
author_rank: Super Contributor
timestamp: August 25, 2014, 01:23:18 am
content: Quote from: SeanB on August 24, 2014, 11:54:03 amSounds like a good idea in theory, except that -1. It requires soaking the board for a while, which means soaking other components that weren't damaged. I don't think that's a terribly great idea. Substituting one cause of reliability problems for another. Also hard to do in some cases, such as a backplane PCB with just a small area of NiCad damage. Can be cleaned and oiled without removing from the machine, but not vinegared and soaked.2. There really are ions diffused into the exposed metals and fiberglass. In my early battles with NiCad corrosion I'd wash, scrub and heat-dry the affected areas very thoroughly, but then after a month the clean metal surfaces would be corroding again. I suspect that the rate of ion diffusion through the metals is quite low, and so surface neutralization and a short soak aren't going to solve the problem.Those were the days when we were all still using NiCads for torches. Stored NiCad D and C cells tended to have that 'grows a fuzz of white whiskers' syndrome. I'd discovered that storing the batteries in oil (either a light coating, or actually immersed in gear oil) completely stopped that. So I tried the same thing on NiCad corrosion damaged boards, after cleaning. It works very well. Only downsides are, can't be used where there is any need for high cleanliness for low leakage current - but then a NiCad corroded board is a writeoff in such cases anyway. Also if exposed to fan-driven airflow the oil/grease picks up dust.Incidentally, the other thing I discovered with NiCads, is that when they develop that self-discharge (or dead short) problem due to the growth of metal whiskers across the plates inside, there's a cure. Connect them to a stick welder, then blat them with 100+ AC Amps very briefly (as quick as you can flip the switch on then off again.) It vaporizes the metal whiskers, and the battery is nearly as good as new.Thank goodness NiCads are no longer with us. Except when discovering the corpse of one has ruined some nice bit of gear.Anyway, I'll try the vinegar then rinse with water idea next time. Then leave the board bare and see if the corrosion returns. If it does, then it's getting oiled. WD40 or white petroleum jelly (vaseline) seem to be OK.

author: Napalm2002
author_rank: Regular Contributor
timestamp: August 28, 2014, 03:41:30 am
content: Love the site. One of my fave reads.

author: HighVoltage
author_rank: Super Contributor
timestamp: August 28, 2014, 11:17:29 am
content: Very informative site, thanks for sharing.You must have a huge room for storage.