How NOT to 'repair' precision measurement equipment (Keithley 6517A), R18+ - Page 1
Forum section: electronics / repair

author: TiN
author_rank: Super Contributor
timestamp: February 07, 2018, 05:06:35 am
content: Well, I didn't think before that I could say "unit is beyound economical repair" about any of Keithley Instruments device I got.But like they say, never say never. My kindness lured me into the trap, I thought I'd give some help toJxw6637and get my hands on 6517A to get some content for my site.I was not prepared at all for what was coming...Unit was packed poorly, just janked into cardboard box with few foam sheets, on the side.As one can guess from white getter spots, VFD glass is definately ruined. This photo was taken after some IPA cleaning already, it was filthy and dirty.It's beyound me how some owners treatinstrument that cost more than $5000USD.What happen to mains jack?!Removing covers for eye-watering sightseeing..Digital boards look okay, no butchery detected there. Firmware is B13-version, RTC battery is good, no burnt parts, everything original.Front panel is same as one used in Keithley 2002, with onboard royer DC-AC-DC converter to drive VFD glass elements.You can see, there is no vacuum in the display. Did it happen from shipping damage due to poor packing, or was like this prior to that, I don't know.Issue is clear, vacuum seal nipple is cracked and destroyed, letting the air in.Nice AUGAT collet sockets for firmware chips and usual Motorola 68000 processor system.This unit had blown transformer, so now it have replaced one. Transformer alone for K6517 cost over $600+ USD. Do not make mistakes like this plugging instrument switched to 110V into 230V mains.No problems here on digital board.I hooked my K2400 front panel board to digital board alone and powered it by Keysight E36312A. Board went online, taking +5V 0.7A. No problems with digital board.As of analog board assembly...I don't have words left to describe, so I'll just let you see on your own...

author: Samogon
author_rank: Frequent Contributor
timestamp: February 07, 2018, 05:15:20 am
content: Speechless

author: MadTux
author_rank: Frequent Contributor
timestamp: February 07, 2018, 05:36:22 am
content: Lol, judging from all that delamination, I presume that one got professionally raped by plumber iron and reckless use of industrial heat gun.BTW, first time I've seen a PIC used in test (or any other industrial) equipment.

author: Zucca
author_rank: Unknown
timestamp: February 07, 2018, 07:57:42 am
content: If not you, nobody can do that miracle here....

author: RobK_NL
author_rank: Frequent Contributor
timestamp: February 07, 2018, 12:07:24 pm
content: This just hurts ...

author: HighVoltage
author_rank: Super Contributor
timestamp: February 07, 2018, 12:13:42 pm
content: Nobody would believe it without pictures.Unreal!

author: Ash
author_rank: Regular Contributor
timestamp: February 07, 2018, 12:29:07 pm
content: This must be what it feels like to be a forensic investigator at your first murder scene..The horror.RIP K6517A.

author: saturnin
author_rank: Regular Contributor
timestamp: February 07, 2018, 05:54:07 pm
content: Given the extend of the damage, I would consider replacing the whole analog board instead of component level repair. Here is one for sale:https://www.ebay.com/itm/Keithley-6517-102-04D-PCB-use-on-6517-electrometer-high-resistance-system/372215905349?hash=item56a9cbfc45:g:QZ4AAOSwL9paZW4t. Seller claims it is in working condition.In case the ADC board will be a leftover after swapping boards, I would be interested in

author: Muxr
author_rank: Super Contributor
timestamp: February 07, 2018, 06:00:29 pm
content: I've seen horrible repairs on TVs or other consumer electronics gear. But why would someone butcher a piece of expensive test equipment like that? Wow. Thanks for sharing.

author: kelchm
author_rank: Regular Contributor
timestamp: February 07, 2018, 09:53:50 pm
content: What kind of person owns a piece of gear like this and is also so incompetent at repair? The mind boggles.

author: andy2000
author_rank: Frequent Contributor
timestamp: February 08, 2018, 02:39:24 am
content: It makes you wonder what they were trying to repair because it looks like the removed and reinstalled virtually every component on the board!

author: Samogon
author_rank: Frequent Contributor
timestamp: February 08, 2018, 05:15:03 am
content: Quote from: andy2000 on February 08, 2018, 02:39:24 amThat is what ya do when has no DMM and oscilloscope.

author: rsjsouza
author_rank: Super Contributor
timestamp: February 08, 2018, 05:18:34 am
content: That's quite a horrid job. In my early days of electronics I have butchered electronic circuits - I can't recall if it was that bad, but it certainly wasn't something >$50 range.

author: ElektroQuark
author_rank: Unknown
timestamp: February 08, 2018, 06:01:07 am
content: Tin, why do you call that a repair?It's clear to me it's a torture.

author: Neomys Sapiens
author_rank: Super Contributor
timestamp: February 08, 2018, 11:18:48 pm
content: Well, when and if the brown wire with the missing insulation coming from the AC input module touches the bare top of the cap, the problems will evaporate. So will the instrument.

author: lowimpedance
author_rank: Super Contributor
timestamp: February 08, 2018, 11:48:50 pm
content: Oh the pain the pain..... my eyes are on fire............. must look away now.Seriously, clearly whom ever did that has no idea when its time to stop, so sad.I see the PCB assembly linked above on Ebay has sold !. That wasn't you TiN ?.

author: bitseeker
author_rank: Super Contributor
timestamp: February 09, 2018, 12:43:52 am
content: * runs away screaming *That's TErrorism.Thanks for sharing, TiN. Can't wait to see it resurrected.

author: joeqsmith
author_rank: Super Contributor
timestamp: February 09, 2018, 12:52:37 am
content: Reminds me when Dave took the Dremel tool to the old LeCroy scope. My sister could have done a better job and she's never touched a soldering iron! Looks like the display was working in the previous thread.

author: imidis
author_rank: Frequent Contributor
timestamp: February 09, 2018, 01:55:06 am
content: I didn't know there were pro's kit branded meters.As to the subject at hand the horror.

author: ArdWar
author_rank: Frequent Contributor
timestamp: February 09, 2018, 02:12:05 am
content: They must be trying really hard when "repairing" it that they managed to damage the chip's package.

author: Cyberdragon
author_rank: Super Contributor
timestamp: February 09, 2018, 05:52:00 am
content: Waiter...my chip is chipped! Also, I didn't order mushrooms on my board, or my IEC well welded!Bah...cosmetic damage by rednecks! Come back when it's been flooded!(...or set on fire, or however you wish to destroy it)

author: Paul Moir
author_rank: Frequent Contributor
timestamp: February 09, 2018, 11:30:57 am
content: Quote from: Cyberdragon on February 09, 2018, 05:52:00 amAs someone who knows welds, those are not welds. Those are short circuits!

author: nidlaX
author_rank: Frequent Contributor
timestamp: February 09, 2018, 11:40:10 am
content: Interesting. I think I might've done a similar job on my first day of learning how to use a non temp controlled soldering iron. Maybe the previous owner was a newbie who got the equipment for ~free and wasn't interested in making a profit? A mis-guided exercise if that.

author: technogeeky
author_rank: Frequent Contributor
timestamp: February 09, 2018, 11:47:05 am
content: What is that bubble in bubble shaped thing? Is that the PCB internally delaminating?Also, with the tremendous amount of damage on this board, there's something poetic about the fact there is still solder in the big electrolytic vias despite the large amount of damage done in those areas. It's like failure and abandonment frozen in time.

author: bitseeker
author_rank: Super Contributor
timestamp: February 09, 2018, 09:49:12 pm
content: Yeah, board is delaminating in many places. Oof!

author: cowasaki
author_rank: Frequent Contributor
timestamp: February 11, 2018, 12:13:54 am
content: This looks like someone tried to do the soldering with a 6" nail in a pair of mole grips. That is absolutely painful.

author: vze1lryy
author_rank: Regular Contributor
timestamp: February 11, 2018, 01:08:43 am
content: The transistors look like they are "taking a bow"

author: Cyberdragon
author_rank: Super Contributor
timestamp: February 11, 2018, 01:11:59 am
content: Quote from: cowasaki on February 11, 2018, 12:13:54 amThey definately used either a large pencil iron or gun iron, likely a hundred watts.

author: cowasaki
author_rank: Frequent Contributor
timestamp: February 11, 2018, 01:19:00 am
content: Quote from: Cyberdragon on February 11, 2018, 01:11:59 amIt beggars belief.

author: james_s
author_rank: Super Contributor
timestamp: February 11, 2018, 01:48:53 am
content: At first glance I thought "That doesn't look so bad" then I started looking more closely and overall that's probably the worst molestation I've ever seen. Most of the individual issues could almost be forgiven but someone has so thoroughly destroyed that board in so many ways that it boggles the mind.

author: wkb
author_rank: Super Contributor
timestamp: February 11, 2018, 09:35:53 am
content: my $DEITY... people who do things like that should be taken behind the shed and shot. What were the actually trying to achieve? Basically everything has been wrecked.. Why? Flamethrower would have been more subtle..

author: cowasaki
author_rank: Frequent Contributor
timestamp: February 11, 2018, 02:48:25 pm
content: I will watch with interest to see how and if this can be resurrected.

author: slurry
author_rank: Regular Contributor
timestamp: February 11, 2018, 04:10:32 pm
content: Ouch.. a clear attempt of blowtorch repair

author: bitseeker
author_rank: Super Contributor
timestamp: February 12, 2018, 03:56:44 am
content: On one of the ICs, it kind of looks like one of the pins broke off near the plastic package and they melted it to get enough solder to bond.

author: Cyberdragon
author_rank: Super Contributor
timestamp: February 13, 2018, 09:05:24 pm
content: Quote from: slurry on February 11, 2018, 04:10:32 pmA torch would have left dark burns. A torch powered iron maybe.

author: Shock
author_rank: Super Contributor
timestamp: February 14, 2018, 12:45:41 pm
content: This is what happens if you use solder wick kids.

author: bitseeker
author_rank: Super Contributor
timestamp: February 14, 2018, 07:18:27 pm
content: Good ol' Weller. Mo' powah!

author: Old Don
author_rank: Regular Contributor
timestamp: February 16, 2018, 08:05:54 pm
content: Take a piece of chalk and draw a pentagram on the floor, place the device in the center of it. Say magical chants and burn some hair of the dog that did this to it and hope that bad juju smites him!

author: nikonoid
author_rank: Regular Contributor
timestamp: February 20, 2018, 08:49:30 pm
content: TiN,I feel you pain. I have a younger brother of your 6517a. My 6517a is much cleaner, but also a redo of previous unsuccessful repair by someone without experience. I fixed VFD and fixed few obvious issues on analog board including leaked capacitors, missing components and eaten traces.My issue is that I also have a blown transformer and cannot even test if analog board repair was successful or not.If you decide not to fix yours, I would be interested in buying transformer from you. I think MM also has 6517a with either digital board or screen blown. We might have options here. Let me know.PS. This is one of my favorite desoldering techniques:

author: TiN
author_rank: Super Contributor
timestamp: February 27, 2018, 04:50:24 am
content: As some mention already, analog board was indeed BER even for crazy volt-nut people, and I was not willing to piss that much time into this unit.So unit owner ended up buying another dead 6517A for donor parts, which had analog board without any attempt of repair, recently fresh too, made in 2011.To fix VFD glass, he got 7001, so I did a glass swap too.That didn't solve front panel issues right away, as one of driver chips was dead, having 3rd grid stick lit. I didn't want to waste too much time on it, so I replaced all driver PLCC chips at once in 10 minutes.Yay, we get no stuck grids, but one character is copied to next grid. Okay, sounds like digital problem, so replaced PLCC MCU on front panel board from 7001 donor FP PCB too. That fixed it completely.Front panel drivers and MCU are same on all dual-line VFD instruments from Keithley, that I know about.VFD brightness is so-so, but it's completely usable level.Then I progress to digital board testing and analog board troubleshooting, minor repair (at this point) and initial diagnostics.This was done over the course of 3hour livestream:.

author: HighVoltage
author_rank: Super Contributor
timestamp: February 27, 2018, 10:10:33 am
content: Quote from: TiN on February 27, 2018, 04:50:24 amYou are definitely the Keithley repair king !Thanks for sharing your repair thoughts.Looking forward to your next video.