Old Fluke Multimeters

[Benzz]

Got a present today: An nice and tidy Fluke 8060a, complete with case and cables and a brief user manual. Seems to work perfect, I am very happy with it. 

[bitseeker]

... finally having unicode support is a blessing. I remember we had to put up a small fight, because Dave was afraid switching to unicode meant having people also write in Japanese, Russian and other languages, but we could provide enough evidence to persuade.
After all, writing a post that looked fine in the preview just to find the posted version missing a bunch of chars just wasn’t right.

Indeed. +1 for Unicode.

[bd139]

Bought an 8010A last week. Perhaps unsurprisingly everything on it worked nicely. Was sealed with last cal in 1986! Was rather grubby and horrible though.  Have finished the second wave of cosmetric restoration now.

Apart from the yellowing on the case, which is expected for the age it looks like new now.



And I just bought a hooky display matching 8012A to go with it 

Edit: while not a massive fan of the display on these, they do the job well enough.

[bd139]

Another refurb - 8012A: https://www.eevblog.com/forum/testgear/fluke-8010a-mains-only-conversion-and-display-replacement/

[WastelandTek]

I've been away for the summer

did we lose Dr. Taylor?

[tautech]

I've been away for the summer

did we lose Dr. Taylor?

Nope.
He looks in from time to time to check on us all......last time was just 3 days ago if you check his profile. 

I'm sure he quite enjoys being called Dr. when in fact they are just his initials. 

[WastelandTek]

Oh good.

I'm just going to call him Dr. anyway, its a Wasteland conferred honorary degree 

[GregDunn]

Again, to avoid filling generic threads with specifics, my new 8600A update/repair thread:

https://www.eevblog.com/forum/repair/fluke-8600a-battery-powered-multimeter-convert-to-line-only/

[elecdonia]

I have a non-battery 8600A; but perhaps it's a good idea to check/replace the caps anyway.  I'm doing a voltage reference comparison right now, but when that's done I can pop it open.  Looks like the electrolytics are easily available values.  Is there any value to replacing tantalum caps too?  I know older HP gear has a problem with them.

I replaced the power supply filter caps in most of my AC mains-powered 8600A units. High ESR is usually the issue with these capacitors. I don't recall changing out any tantalum caps so far.

By far the most common issue with battery powered 8600A is needing to replace the 4000mAh NiCd cells.

Both line-powered and battery-powered units 8600A units often have bad connections at the large male pins that connect to the daughter cards.

Another fault I noticed recently is drifting zero offset when first powered up after several months of non-powered storage. I think this comes from leakage currents flowing through dirt on the PC board surfaces. Thorough PC board cleaning/drying seems to correct this issue.

[med6753]

I have a non-battery 8600A; but perhaps it's a good idea to check/replace the caps anyway.  I'm doing a voltage reference comparison right now, but when that's done I can pop it open.  Looks like the electrolytics are easily available values.  Is there any value to replacing tantalum caps too?  I know older HP gear has a problem with them.

I replaced the power supply filter caps in most of my AC mains-powered 8600A units. High ESR is usually the issue with these capacitors. I don't recall changing out any tantalum caps so far.

By far the most common issue with battery powered 8600A is needing to replace the 4000mAh NiCd cells.

Both line-powered and battery-powered units 8600A units often have bad connections at the large male pins that connect to the daughter cards.

Another fault I noticed recently is drifting zero offset when first powered up after several months of non-powered storage. I think this comes from leakage currents flowing through dirt on the PC board surfaces. Thorough PC board cleaning/drying seems to correct this issue.

That drift could also been caused by this........

https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg1974341/#msg1974341

Took me quite a while to track it down but it is now absolutely rock stable.

[DC1MC]

I have a Fluke 8800A waiting for reanimation (initial symptoms: faint red range LED, no reaction to buttons, former owner broke the the green paddle and put acetone to glue it back managing to melt it on the case  ).
Because I was felling in need of (relatively) instant gratification, I've open it, changed the usual basterds (see the picture, trifecta, Sprague, Phillips and and MEPCO, this one on the 5V being actually 16pF !!!) and the old girl sprang to live, the initial readings had some offset but were stable enough, except for the high voltages ranges, where it was a real noise +/- 15%, egal what voltage was applied.
After cleaning all the contacts, carefully marking the position of the trimmer potentiates and exercising them few times, everything stabilized nicely EXCEPT for the bloody zero on short, this was moving in between +70 and+ 20 on the ends of the front panel zero trimmer  , I was preparing to replace the main adjustment resistor, as the manual suggest, realized that I have none and staring to feel bad, but while moving the device on the table the zero offset I've seen some mechanical variation on the reading with the input shorted.

 Long story short, the bloody range relay it's a POS, I've clean it as good as I could, put it back and I've got a minimum value of +14 and stable, exercising it by putting on and off a 150V to switch the relays reduced it to 6 and that was it, no way to go lower, but at least now it's really rock stable, the 10V in the picture are staying like this for 2Hrs and I'll let it run over night, so mission (almost) accomplished  .

Now I have a couple of questions for the Fluke gang:

- Any NOS or other replacement for the ranging relay available somewhere  ?

- Anybody in DE/EU has a donor unit and willing to send me the green (or any paddle) to replace the power supply Pfu­sche­rei ?

- Any ideas for the zero adjustment WITHOUT replacing the main calibration resistor if I can't get a new relay ?

 Finally after almost 2 1/2h it started to blink 10.0000/9.9999, I'm taking bets for tomorrow for the drift  .

 Cheers,
 DC1MC

Obligatory pictures attached  .

[GregDunn]

Same caps I replaced on mine and it was resurrected almost immediately.  That, plus a couple of nasty solder joints on the Ω board, were all that was keeping it from its full glory.  Well, that and dirty switch contacts.

I have cleaned the big relay on mine as well, and it seems to be stable.  I haven't seen any option for replacement, unlike the little reed relays.

The previous owner broke the power switch on mine as well, but he did a superb job of repairing it.  Perhaps we should keep an eye out for 88xx front panels on the Bay, and accumulate a small stock of spares?

[DC1MC]

Same caps I replaced on mine and it was resurrected almost immediately.  That, plus a couple of nasty solder joints on the Ω board, were all that was keeping it from its full glory.  Well, that and dirty switch contacts.

I have cleaned the big relay on mine as well, and it seems to be stable.  I haven't seen any option for replacement, unlike the little reed relays.

The previous owner broke the power switch on mine as well, but he did a superb job of repairing it.  Perhaps we should keep an eye out for 88xx front panels on the Bay, and accumulate a small stock of spares?

The ironic part is that 30yrs ago I was working with similar relays like the big one, they were crappy then as well, I can't imagine why Fluke has chosen it, maybe a cost reduction measure 
Anyways it looks like gold coating on it, but it's just yellow metal (bronze-beryllium ?), it was some oxidation on the contacts that it polished off, so far I'm extremely pleased with the stability, it didn't drifted at all on 10V, tomorrow I'll put my 1,10 and 100K resistors to test the ohms board, the soldering was looking OK, but who knows.
If I could get rid of this miserable zero offset shift then can calibrate it properly.

Speaking of spare parts, chances are slim in DE/EU, the US seem to be awash in 88xx, as usually, I've seen two of them on this strange site that  I was asking before, I'll give it a try to the 8810 with the PayPal.
If you get some, we can split the parts, I also need one of the rubber feets, but at lest the handle is perfect  .
I'm still amazed that is almost 40years and still works nicely, and it come really cheap (for DE).

 Cheers,
 DC1MC

 

[GregDunn]

I'll probably be picking up another 1 or 2 8800A units as soon as I get the current queue shortened a bit.     If they're cheap enough I'll probably do what I've been doing with the 8600A - picking up broken units for repair or possibly just spares.  If that happens I'll surely have some pieces to split off.  I'm not too bothered by having handles on my equipment, but without feet it's a pain to get them to sit stably on the shelf...

The goal is just to have 2 each 8600A and 8800A running eventually, with enough spares to make sure they stay that way.    

[DC1MC]

I hammered the bloody big relay until I got some +1 count for zero, but this thing is ridiculous, such a nice and stable instrument hindered by this crappy thing, now I've seen that somehow the moving part dig a small trench in the support and with the plastic cover on, it never settles in the right position, I discarded the plastic crap, but still I have to find a long term solution to this.

Any advice is welcome, my idea is to get a modern 4,5V relay, throw away the old one and the socket and solder it on a small board or with flying wires.

Any other ideas and replacement solutions are welcome.

 Cheers,
 DC1MC
 

[GregDunn]

Ordered a parts/broken 8600A last week with the hope of synthesizing a working unit from the two non-working ones.  Surprise!  After temporarily inserting 5VDC in place of the dead batteries, it came to life and works a treat:

https://www.eevblog.com/forum/repair/fluke-8600a-battery-powered-multimeter-convert-to-line-only/

It seems that for me, the "broken" Flukes take little effort to fix, and the "working" ones have complex problems.   

[DC1MC]

@GregDunn, lucky you, this never happens on my side, and I was looking for a defective unit, no luck .

I've got a couple of ITT relays C93406 MT2 4, hoping that I'll replace the big POS for range selection.

 Still looking for a paddle for the power switch.

 Cheers,
 DC1MC

[GregDunn]

They do exist, but it takes some patience; right now there seems to be a shortage of 8800A units of either type, but several 8600A came up recently so I thought I'd work on that side of the collection.  Unfortunately, people love to get rid of their Option 01 battery units, which not only are invariably dead but have collateral damage on the PCB from leaky NiCd cells.  I want no more of those!  Even if the cells don't spew corrosion onto the mainboard, they vent something which oxidizes the circuit traces and connector pins.     It's hard enough to troubleshoot some of these without repairing traces and connectors as well.

I've promised myself that as soon as I get as many of the 8600A running as is feasible, I'm going to stop and move on to the 8800As.  At least those are free from the battery plague, even if they're missing a current measuring mode.

[Neomys Sapiens]

Is there somewhere a published timeline and development relationship of their gear? At least up to the marriage with Philips?

[001]

Bought an 8010A last week. Perhaps unsurprisingly everything on it worked nicely. Was sealed with last cal in 1986! Was rather grubby and horrible though.  Have finished the second wave of cosmetric restoration now.

Apart from the yellowing on the case, which is expected for the age it looks like new now.



And I just bought a hooky display matching 8012A to go with it 

Edit: while not a massive fan of the display on these, they do the job well enough.

Awesome works 

Can You told me how "siemens" reading works? When do You use it?

[bd139]

Conductance is the reciprocal of resistance.

Basically you can use it to measure high resistances (up to 10Gohm), leakage and semiconductor junction characteristics (pop one on a phototransistor for example). If you build the fixture described in the manual you can also measure transistor DC beta and leakage too. Pop the value in calculator and press reciprocal to get ohms back.

It makes sense to work in conductance as the scale of the values is different to ohms.

If you have the 8012A (I do) you can cal out the probe resistance on 2 wire mode and measure resistance down to 0.001 ohms which is good for tracing out board shorts due to tantalum capacitors!

Historically I used to use one with a fixture to classify bags of crappy old germanium transistors to sell to guitar pedal builders

Not bad for an old junker of a meter!

[001]

Conductance is the reciprocal of resistance.

Basically you can use it to measure high resistances (up to 10Gohm), leakage and semiconductor junction characteristics (pop one on a phototransistor for example). If you build the fixture described in the manual you can also measure transistor DC beta and leakage too. Pop the value in calculator and press reciprocal to get ohms back.

It makes sense to work in conductance as the scale of the values is different to ohms.

If you have the 8012A (I do) you can cal out the probe resistance on 2 wire mode and measure resistance down to 0.001 ohms which is good for tracing out board shorts due to tantalum capacitors!

Historically I used to use one with a fixture to classify bags of crappy old germanium transistors to sell to guitar pedal builders

Not bad for an old junker of a meter!

How do You do it? transistors and siemens 

[GregDunn]

Well, this was a happy Wednesday.  Even though I made a couple of puzzling discoveries about my recently acquired 8600A (see other thread in Repair) I was pleased to see a box arrive on my porch, this time a line-powered 8600A in "broken" condition.  My goal, as mentioned, is to have at least 2 of these working on the bench, but so far the count was only at 1.5 working meters.     Would this one break my unlucky streak?

As mentioned above, the broken ones seem to be in better shape than the working ones.     This one was immaculate inside and out except for the missing bail/stand (as listed).  I never use them anyway, so the fact that it was essentially un-scarred, especially the faceplate, was a fine tradeoff.  Nothing looked obviously zorched or broken.  I expected a power supply issue, so I put it on the variac and looked at the +5 and ±15VDC as I brought the voltage up.  They looked fine; no excessive current draw, voltages balanced.  Well, OK, at least it's not going to blow up.  So I brought the variac to 100% and - click, click - the display lit up and relays switched.  I did a quick check on Ω with short, open and 1K - all passed, with autorange doing its job.  DCV from the calibrator - up to 100V, tracking nicely.  ACV from the calibrator - ditto.  Now, to the DCA mode.  Calibrator output light flickered and meter read 0.  That usually means a bad connection (blown fuse?) so I unplugged everything and pulled the fuse holder.  The fuse was fine, but the little spring contact was no longer soldered firmly to the board; it was barely touching the fuse.  Sadly, I'm going to have to take the meter all apart to repair it due to its buried location, but I'll bet that's why the meter was listed as broken.  I'll be very surprised if it fails to work once I've repaired the connection.

Not only functioning, but in calibration, as you can see from it measuring the voltage standard of 10.0032 VDC!   

Edit: Managed to solder the spring contact back into place and indeed the DCA and ACA modes work a treat.  Hurray for broken $20 Flukes!

[GregDunn]

Currently working on a "for parts" 8800A which may require a donor unit to revive:

https://www.eevblog.com/forum/repair/fluke-8800aaf-power-supply-parts/

The PSU was fixed easily, but it's beginning to look as though the U11 controller is dead - no timing signals even though the clock signal is present at the input.  I hate to make this one a donor because it's in excellent shape inside and out, and has the late model Ohms board.

[GregDunn]

And here's another reason why I buy these in pairs.  Just like the 8600A meters I picked up recently, one 8800A was DOA and the other is - fully operational.  The hope was that between the two of them I could get one meter working, and that's exactly what I got.  This one powered up (as promised) but also seems to meet its specs just fine.  DCV and ACV are as good as I can detect, including comparison with the other Flukes.  The Ω range also matches my other meters against the PRC resistance "standard" I have.  Pretty good for $35.

A question for the Flukesters out there: does anyone know what SN the 8800A started shipping with the battery-less ohms board?  My 258xxx meter has it, and so does the 286xxx unit.  This one is 276xxx and I confess I haven't popped it open yet because it still has a sealed cal sticker from 1999 and I'm not quite ready to tear it off.  The fact that Ω is still in spec after 20 years of no maintenance makes me think it's one of the newer boards, as well as the SN being later than my first unit.  I will have to open it eventually for inspection and capture another data point, but the question has been on my mind for a while.