Fluke 8060A Somewhat Functional

[CatNinja]

If you’ve handled the board a lot, you may have got some oils from your hand on the board. These Fluke multimeters are very sensitive to current leakages between the traces.

I was wracking my brains out trying to figure out why the readings were off and inconsistent when repairing mine, and it all went away after I washed the board in isopropyl. Try to use just enough alcohol to submerge the board, and not get it into the switches.

Make sure to look very carefully under the caps. Sometimes the leakage is hard to see until you remove them.

The switches are the same between all the multimeters in this series. You can get a broken 8062 very cheaply for parts.

You probably do not even need to recalibrate after repairing. These things are dead accurate even after 30 years. My favorite multimeter by far.

[J-R]

If R2 is fine, then the other entry under the troubleshooting for
"DC readings correct for
200 mV, 2V-incorrect
for 20V, 200V, 300V"

is: "Input divider or input divider switches" (table 5-7 in the manual)

Also, if you can find other functions that aren't working, you could cross-reference the two in order to find a common failure point.

[Christine1953]

I was wracking my brains out trying to figure out why the readings were off and inconsistent when repairing mine, and it all went away after I washed the board in isopropyl. Try to use just enough alcohol to submerge the board, and not get it into the switches.

Make sure to look very carefully under the caps. Sometimes the leakage is hard to see until you remove them.

I'll give that a shot. So it's OK if the IC's get wet? Might be a dumb question, but I work mainly on tube amps and you know LOL, you usually don't run into things like this. I'm learning a lot, and if I can get this meter going, I'll feel like I accomplished something big! I'm going to replace all the caps, I'm good at soldering, have all the tools I need for that, and the board  looks super well made. I'm just waiting to see if someone might have a BOM for the caps. I'm thinking looking all those up is going to take some time,   Thank you!

[Christine1953]

If R2 is fine, then the other entry under the troubleshooting for
"DC readings correct for
200 mV, 2V-incorrect
for 20V, 200V, 300V"

is: "Input divider or input divider switches" (table 5-7 in the manual)

Also, if you can find other functions that aren't working, you could cross-reference the two in order to find a common failure point.

I'm reading about that now in the service manual. The switches work properly for ohms, but, who knows for the other functions. I'm setting up a jig to test amps and AC voltages, but not until Monday. Someone else mentioned looking at the MOV's in the protection circuit. If I remember correctly (like almost 30 years ago), this meter broke down as someone was using it checking voltages in the hi voltage section of a CRT monitor. So more detective work is needed... Thanks!

[CatNinja]

PCB, IC's, passives are fine washed in isopropyl. Switches are OK too, but really need to be taken apart to clean properly, and you may have to re-lubricate for them to work properly, so best to leave them alone. Plastic parts tend to deteriorate if left in isopropyl too long, so OK for a quick wipe down, but I wouldn't soak them (test first!).

Make sure you use 99%, as you do not want water left between the components, which will cause corrosion. Don't soak too long (just scrub with soft brush and rinse), dry off with a fan to speed it up, and don't reuse solution (it will just re-deposit whatever was dissolved).

An ultrasonic cleaner is ideal if you have access to one.

You can also use dedicated electronics cleaners, but those are very expensive and don't work that much better in this case.

Here are my notes for the recap. I don't remember which ones I got, so double check the specs before ordering. The hard one to find is the 22uf, as the poly one recommended by drtaylor is discontinued. I ended up getting a non-polymer, high quality cap instead. I listed a few alternatives at the bottom.

nichicon polymer 5000h (recommended by drtaylor)

RS61C101MDS1    5x      nichicon 100uf 20% 16v 105c 5000h 6.3x8x2.5     C1,C23,C24,C32,C34
RNU1A100MDS1    3x      nichicon 10uf 20% 10v 105c 5000h 4x5x1.5        C12,C21,C28
UTT1C220MDD1TP  1x      nichicon 22uf 20% 16v 105c 5000h 5x8x2          C36     obsolete
RNS1C470MDS1    1x      nichicon 47uf 20% 16v 105c 5000h 6.3x10x2.5     C19

alternatives (double check that size fits)

493-6018-ND             nichicon 100uf 20% 6.3v 2000h 6.3x7x2.5
493-10382-1-ND          nichicon 100uf 20% 6.3v 105c 2000h 6.3x7x2.5
RS81C101MDN1JT          nichicon 100uf 20% 16v 105c 2000h 6.3x8x2.5
16SEPC100M              panasonic 100uf 20% 16v 105c 5000h 6.3x6x2.5    polymer
APSF160E101MF05S        chemi-con 100uf 20% 16v 105c 20000h 6.3x5x2.5   polymer
A750EK107M1CAAE18       kemet 100uf 20% 16v 105c 2000h 6.3x8x2.5

USR1C100MDD-ND          nichicon 10uf 20% 16v 2000h 4x7x1.5
493-10390-1-ND          nichicon 10uf 20% 16v 105c 2000h 4x7x1.5

493-6027-ND             nichicon 22uf 20% 16v 2000h 5x7x2
493-10393-1-ND          nichicon 22uf 20% 16v 105c 2000h 5x7x2
EEA-GA1C220             panasonic 22uf 20% 16v 105c 1000h 5x7x2
EKMA160ETD220ME07D      chemi-con 22uf 20% 16v 105c 1000h 5x7x2
226PGM016M              cornell-debilier 22uf 16v 20% 105c 1000h 5x7x2
25ML22MEFC5x5           rubycon 22uf 20% 25v 105c 3000h 5x5x2           long-life
16ZLG22MEFC5x7          rubycon 22uf 20% 16v 105c 1000h 5x7x2           low-esr 270mohm
16MH522MEFC5x5          rubycon 22uf 20% 16v 105c 1000h 5x5x2           general-purpose

493-6026-ND             nichicon 47uf 20% 10v 2000h 6.3x7x2.5
493-10396-1-ND          nichicon 47uf 20% 16v 105c 2000h 6.3x7x2.5
35SEK47M                panasonic 47uf 20% 35v 125c 1000h 6.3x6x2.5     high-voltage
EEA-GA1C470             panasonic 47uf 20% 16v 105c 1000h 6.3x7x2.5     general-purpose


Edit: cleaned up parts list and added a diagram I found in my notes folder

[AVGresponding]

Also, don't get IPA in the fuses; someone in another thread, on an Agilent 12-something or other did and it ruined them.

[vindoline]

Check the input protection MOVs. They look like little colored resistors in the bottom right of the PCB. I have found that if the meter is briefly overloaded (easy to imagine in a broadcast setting) they increase in resistance and cause all kinds of weird and wonderful accuracy problems.

Are these guys the ones you're talking about in the protection circuit? I think I read something about when you're on the 200mv or 2v settings this circuit is bypassed??? Could we just jumper around the protection circuit to test? As I said in my last post, both the 200mv, and 2v sections are working correctly, at least with DC. As for checking the MOV's if they're good/bad, I'd have no idea how to do that.
 
To be honest, I've suspected something might be amiss here, as I remember another tech telling me the meter stopped working while he was poking around in the high voltage section of a CRT monitor.  The DOA part came right after as we were trying to figure out what happened to the meter. It just completely quit working. My guess it was two unrelated problems. Let me know your thoughts. Thanks!

Yes, components J1 to J4. They should be essentially short circuit under normal circumstances. They go permanently high resistance if exposed to high voltage. You should be able to jumper them to test, or just test the resistance with another meter.

[robert.rozee]

Yes, components J1 to J4. They should be essentially short circuit under normal circumstances. They go permanently high resistance if exposed to high voltage. You should be able to jumper them to test, or just test the resistance with another meter.

if you are talking about RJ1 to RJ4 in the below schematic, these should all measure open-circuit:




cheers,
rob   :-)

[vindoline]

Yes, components J1 to J4. They should be essentially short circuit under normal circumstances. They go permanently high resistance if exposed to high voltage. You should be able to jumper them to test, or just test the resistance with another meter.

if you are talking about RJ1 to RJ4 in the below schematic, these should all measure open-circuit:




cheers,
rob   :-)

Must be poor memory on my part! Thanks. Of course, if I actually looked at the schematic, that would have been obvious!

[Christine1953]

First off, thanks everyone! It looks like I have my work cut out for me over the next day or two. I'm taking today off (spring cleanup in the Northwoods). So tomorrow, I'll start working on the list I've created, which is long... Maybe we can all look at the results and a light bulb will go on. I keep getting the sensation that I'm overlooking something basic, but I've been down this road before many times, and all of a sudden you have this "a-ha" moment LOL!

Here's my list and feel free to add to it if you see something missing.

Clean the main board with the fuses removed with IPA.
Check to see MOV's read like they're "open" (infinite resistance).
Fix or bypass DC barrel.
Check functions on, AC/DC volts, AC/DC current, and top row buttons, at least for LCD function at this point.
Put together a BOM for the electrolytic caps and order from digikey
Order a new set of probes. (Just because I deserve something out of this).

Everyone have a great weekend, and I'll be in touch Mon or Tues. And, feel free to post, I'll be checking the thread through the weekend.

Thanks for the encouragement and support!

[J-R]

In my opinion, for this design of switch you should be able to get away with cleaning them without removal.  Hold the PCB vertically with the switches facing down, then spray some non-residue contact or other cleaner into the top and open end of the switches while working them.  I usually give them all a quick spray, then work the switches a bunch, then spray again.  Then you don't contaminate the PCB.