Fluke 83V vs 87V - Spot The Differences!

[gamalot]

I found three obvious differences, can you find more? 



This image of the Fluke 87V below is from a post by forum member @SerjP: https://www.eevblog.com/forum/testgear/fluke-87v-(2021)-teardown/

[tautech]

Labels are different ! 

[timenutgoblin]

Not sure if it's obvious because I didn't see it immediately.

Both PCBs have a hybrid resistor network located below an LT/Fluke IC and further below, along the bottom of the PCB, there are four components as can be seen in the top photo. However, the two grey coloured capacitors are omitted in the bottom photo.

[Mechatrommer]

i remember i won a spot the difference contest and brought a KFC bucket home as a prize...

[coromonadalix]

And the question would be     

Can we convert an 83 into an 87 ??  is the firmware extractable ?

[Arhigos]

83v Missing transistor under 440mA fuse  (not visible on pictures)

[AVGresponding]

There are a few parts you can't see that are missing from the 83, mostly to do with the LPF and the MUX it switches through, afaik. Other than that it uses the same parts, including the same A grade of LT1790-2.5, which does make me wonder what accounts for the specified difference in performance in the non-AC ranges. More careful calibration and adjustment at the factory?
The Hi-Res mode on the 87 is sw rather than hw, as evidenced by the bug in the lower current ranges.

As long as the MCU is reprogrammable I guess you could just load an 87 fw, add the parts, and have an 87V.

[gamalot]

Although the user manual only gives 83V AC performance below 5KHz, it works fine at 20KHz in the tests I've done.

Getting 87V firmware should be mission impossible, trying to save money by buying an 83V and converting it to 87V is a waste of life, except for fun. 

[Mechatrommer]

Getting 87V firmware should be mission impossible, trying to save money by buying an 83V and converting it to 87V is a waste of life, except for fun. 

not impossible, unless what you meant is Tom Cruise style mission impossible movie. such as wait for a broken 87V in ebay and remove the chip to 83V. waste of money as well since calibration is a part of money you paid, and doing the mod is risking screwing or redoing the calibration. btw, another spot the difference spotted... no white mark on the knob for 83V! someone mourned about that recently, i'm going to forward the picture there. https://www.eevblog.com/forum/testgear/fluke-87v-switchs-white-mark/?topicscreen

[AVGresponding]

It is possible to recalibrate, but I'd also agree there seems little point other than as a challenge, just much easier to get an actual 87V.

[Mechatrommer]

surprisingly last night i checked in ebay US, you can get cheaper 87V than 83V... grey market or not is another story.

[Arhigos]

Technically you can add true rms feature just by soldering missing components

[gamalot]

Yeah ... nah, I saw this video when it was just released, fun to try but not worth it, especially when you have too many multimeters, you're happy to have an average meter instead of RMS like the rest. 

[tooki]

surprisingly last night i checked in ebay US, you can get cheaper 87V than 83V... grey market or not is another story.

While the list price of the 83V is slightly lower, my guess is that the volume sold of the 83V is tiny compared to the 87V, such that dealers are able to negotiate far better volume discounts on the 87V, explaining why some dealers charge the same for both, sometimes even more for the 83V!

It also maybe means that far more 87V units are available on the used market, pushing down the price a bit.

[tooki]

Getting 87V firmware should be mission impossible, trying to save money by buying an 83V and converting it to 87V is a waste of life, except for fun. 

not impossible, unless what you meant is Tom Cruise style mission impossible movie. such as wait for a broken 87V in ebay and remove the chip to 83V. waste of money as well since calibration is a part of money you paid, and doing the mod is risking screwing or redoing the calibration. btw, another spot the difference spotted... no white mark on the knob for 83V! someone mourned about that recently, i'm going to forward the picture there. https://www.eevblog.com/forum/testgear/fluke-87v-switchs-white-mark/?topicscreen

Both the 83V and 87V originally had the paint line, now they both don’t.

[BeBuLamar]

Fluke keeps the 83V in production (they don't have the 85V) not for people who doesn't want to pay the price of the 87V but for people who don't want true RMS. Fluke priced them about the same price. So it makes no sense trying to make the 83V to be the 87V.

[Fungus]

Fluke keeps the 83V in production (they don't have the 85V) not for people who doesn't want to pay the price of the 87V but for people who don't want true RMS. Fluke priced them about the same price. So it makes no sense trying to make the 83V to be the 87V.

AFAIK the 83V is also lacking the hi-res mode and is less accurate.

Most users probably don't care though, 6000 counts and 0.1% is plenty accurate for most jobs.

[BeBuLamar]

Fluke keeps the 83V in production (they don't have the 85V) not for people who doesn't want to pay the price of the 87V but for people who don't want true RMS. Fluke priced them about the same price. So it makes no sense trying to make the 83V to be the 87V.

AFAIK the 83V is also lacking the hi-res mode and is less accurate.

Most users probably don't care though, 6000 counts and 0.1% is plenty accurate for most jobs.

Mainly if you buy the 83V it's because you want everaging meter not so much on saving money. To save money you would go to the 17x series.

[Fungus]

Mainly if you buy the 83V it's because you want everaging meter not so much on saving money. To save money you would go to the 17x series.

I'm sure there's many written test procedures and manuals out there that rely on using averaging meters.

[andyB2022]

Although the user manual only gives 83V AC performance below 5KHz, it works fine at 20KHz in the tests I've done.

Getting 87V firmware should be mission impossible, trying to save money by buying an 83V and converting it to 87V is a waste of life, except for fun. 

As I see from your picture, the rotary knob of the meter does not have the little arrow painted in white. Is this common? I've seen another meter these days and I've thought it might be a knock off.

[gamalot]

As I see from your picture, the rotary knob of the meter does not have the little arrow painted in white. Is this common? I've seen another meter these days and I've thought it might be a knock off.

This is normal, IIRC there is another thread discussing it.

[andyB2022]

I'm sorry, what does IIRC mean? Do you have a link to that thread?

[gamalot]

I'm sorry, what does IIRC mean? Do you have a link to that thread?

IIRC = if I recall correctly

https://www.eevblog.com/forum/testgear/fluke-87v-switchs-white-mark/