Fluke 87 III pictures?!

[Marvin]

I really tried to google it but seems that there are NO internal shots of this meter available anywhere?! The closest I could find was this picture of the custom chip in the original 87 series.

This is the board (nicely burnt)

There was a really low quality shot of the back side of an original 87 in the forums but can't find it at the moment.

I know that Fluke provides the full service manual for the original 87 series and looking at 87 III calibration guide the board placement is almost the same as the original - but how are the guts of this legendary meter impossible to find? Seems to me that 87 III vs 87 V should be looked as almost 2 different multimeters. III is "full analog" with analog calibration and a custom chip vs the V "full digital" with a programmable microprocessor (and it really is programmable, Fluke seems to reprogram it when calibrating, more information @ https://www.eevblog.com/forum/product-reviews-photos-and-discussion/fluke-87v-pcb-revision-check-before-purchase/). III with hand drawn PCB, V with computer aided design. III has only AC/DC voltage calibration, V has full calibration from resistance, capacitance etc...

Of course they are different classes of multimeters but judging by the original 80 series schematics the pre V series is more closer to a 17B (that lacks analog bar and RMS) than the V (that seems almost a complete redesign).

Has everyone moved on to the 87 V and no one left to tear the 87 III (or the original series) open and take pics?

[glicos]

Luckily still got my 87 III...

[Marvin]

Thanks man! I literally googeled for days to find these with no avail. Dave should do a teardown and a detailed comparison against V of this! It is a mixed bag of smd and thru-hole components! No gold covered contacts but oldschool round switch. But it is nicely computer traced, I guess the picture I remember was an original series 87 (I) that looked like it had rounded corner traces.

The back side smd chips are aligned like some made in China stuff (HC4538A and the chip underneath it).

But take a look at the button contacts - the ones on the burn one I found are wavy style like the new ones, yours is traditional line styled. I guess like the Fluke 27 that Dave tore down had a really late life revision the later III models were more like the V is. And the mode switch looks like a V styled on the burnt one.

[Marvin]

Here is the older thread that shows even an older revision, yours is 8X-3-3001 Rev B, this is 8X-3001 Rev V (or N) of original 87 series.



https://www.eevblog.com/forum/general-chat/help-with-new-(to-me)-fluke-87iii/msg22430/#msg22430

The 87 series has really gone thru a lot of revisions and models.

[saturation]

On pot calibrated DMMs, you can work on any range that is off, but I luckily have not had to do so on my Flukes. 

I don't have an 87III but I do have an 85III and and 85I.  For this series DMMs I prefer the older I and III series because of the pot adjusts and I have full service manuals.  On the 87V, its impossible without a proper calibrator because it requires specific calibrator references, in a strict sequence, that is all or none [ yes, I have an 87V too]. 

However, one advantage of the Agilent DMMs: I adjusted a slightly off Agilent 1252a and 1272a because it does allow adjustment of any single or set of ranges, and will accept any reference value, yet its all digital.