Old Test Gear Restoration Questions - Page 1
Forum section: electronics / beginners

author: Rerouter
author_rank: Super Contributor
timestamp: January 26, 2012, 06:54:02 am
content: A task that i feel a number of us have faced in the past, you salvage a piece of test gear in one way or another, and it doesn't work or only works to some capacity,Recently i have had to repair quite a few bits, and felt i would ask peoples opinions on methods of repairing gear,be it a 10 year old power supply, or a 50 year old radio,Manuals:While a lot of manuals can be sourced from BAMA or the manufacturer, are there any more obscure manual archives?Cleaning: Now i realise the common chemical might be isopropl, but what about for those jobs with sticky residues, or other non common filth, what do you use to apply it, a brush?, a cloth?, maybe just pour it on and go over with an air compressor?Capacitors:Such as tantalums and electrolytic, do you go full out and swap out all the tantalums, or only those you suspect, and what do you replace them with, with electros do you also swap them out, or leave them alone if they read a correct value?Soldering:Do you just jump in and go over dry joints, or perhaps clean it in some method before approaching them, perhaps use some special solder like 2% silver, or some special flux, or avoid as much as possible?

author: Unknown
author_rank: Unknown
timestamp: January 26, 2012, 11:35:12 pm
content: Quote from: Rerouter on January 26, 2012, 06:54:02 amFree:http://ko4bb.com/manuals/http://www.ebaman.com/http://manoman.sqhill.com/http://128.238.9.201/~kurt/manuals/Paid (if free sources fail):http://www.artekmedia.com/http://qservice.tv/Dead tree versions ($$$):http://www.manualsplus.com/Quote from: Rerouter on January 26, 2012, 06:54:02 amEither a cloth, brush or Q-tip, depending on the kind of surface and dirt. I don't like to pour it directly on some equipment, this makes it hard to control where it will go, it may seep into places where I don't want it.Quote from: Rerouter on January 26, 2012, 06:54:02 amI don't believe in large-scale parts replacements, too much risk damaging the PCB or accidentally reversing polarity. It's not like those modern electrolytics are expected to last forever. I only replace shorted tants, leaking aluminum electrolytics or electrolytics with high ESR (causing a too large ripple on the supply rails). Exceptions are if the PCB is very hard to access, or if they're likely to cause damage, like the SMT electrolytics in the later Tek 24xx series.Quote from: Rerouter on January 26, 2012, 06:54:02 amI wouldn't mix lead-free with lead-bearing solder, so use lead solder. 2% silver only if the original components contained silver, like the ceramic terminal strips used in tube-era Tek scopes. I don't usually pay that much attention to flux (either no clean or RMA), though I'll be sure to clean it in high impedance circuits.

author: sonicj
author_rank: Frequent Contributor
timestamp: January 27, 2012, 03:46:37 am
content: i like using a spray bottle for IPA. various brushes, air compressor, medical q-tips, kimwipes, acetone as necessary (not on plastics)-sj

author: saturation
author_rank: Super Contributor
timestamp: January 27, 2012, 10:50:50 am
content: Overall great resources to other great resources, check the links first, then search the content for manual sources:http://tech.groups.yahoo.com/group/hp_agilent_equipment/?yguid=146639433http://groups.yahoo.com/group/Manual_Exchange/http://tech.groups.yahoo.com/group/TekScopes/http://tech.groups.yahoo.com/group/TekScopArc/

author: Unknown
author_rank: Unknown
timestamp: January 27, 2012, 10:56:21 am
content: I believe there's also a TekScopesArc2 group because they ran out of space in the first one. Not sure how much manuals they contain.

author: w2aew
author_rank: Super Contributor
timestamp: January 27, 2012, 02:42:36 pm
content: For what it's worth - my favorite source for reproduction manuals for Amateur Radio, Audio, antique radio and other things (not as much test equipment) is The ManualManhttp://www.manualman.com/.