The Heathkit IM-2215 Portable Digital Multimeter

[@armstronglance]

Still have mine! My Fluke, Kelvin & IBM multimeters have all bit the dust, but this Heathkit one lives on!!!

[@ripjones5294]

Very interesting. I built several Heathkits during their lifetime. I still have several pieces of their test equipment -- HV and LV power supplies, as well as RF. I built this 2215 when it was available. I took it to the mill where I worked, and it was stolen. It was out of production, so I could not replace it. In reality, this was actually a Fluke meter that was turned into a kit by Heathkit. I have subscribed.

[@youtuuba]

Rip Jones, actually this was NOT a Fluke meter in kit form. But Heathkit did, on occasion, base their own designs on older existing commercial designs, and based on circuit study I agree that some of their test equipment has a pedigree from companies like Tektronix and Fluke and others. But the cases, PCBs and physical design was quite different, and they always economized the circuit and components to allow a more hobbyist-accessible selling cost. So it would be more accurate to say this meter was based on an older Fluke meter design, rather than it WAS a Fluke product in kit form.

[@youtuuba]

This was actually a pretty good meter. I always considered buying one, but by the time it was available, I already had a couple Fluke and Keithley DMMs, and could not justify buying a lesser meter than those just to build another kit. But recently I bought and restored one of these, and did a detailed analysis of the circuit, and it was quite well thought out and 'solid'. As with another Heathkit meter in this series, their handheld digital capacitance meter, the Achilles heel on both was the non-sealed, minimal wiping-action slide switches through which all input signals pass.....being unsealed allowed Heathkit to save some money and offer a lower priced product, but it also meant that many of these stopped working long before anything ELSE inside also quit. Unfortunately, it is very hard to get those switches working again, other than cycling the switches a lot in hopes of restoring better contact continuity.

[@gh778jk]

Just ordered your book ! Looking forward to reading it! 73 Paddy

[@watchmakerful]

Is this a predecessor for the Soviet multimeter Electronica MMC-01?

[@garyrogers726]

Jeff, excellent report on the 2215. Which Video Camera did you use to record this session. I would like to know the make and model number as your video quality is excellent and I would like to purchase a camera like it. Thanks for the reviews, excellent information. Gary

[@jefftranter]

Thanks Gary. The camera I use is a Nikon CoolPix P7000.

[@douro20]

Do you have an IT-18 transistor checker? I've used mine quite a lot to check old germanium transistors. I've also used it on occasion for gain matching as it is very accurate.

[@jefftranter]

No, I don't have any Heathkit transistor testers. I am keeping my eye out for one.

[@ripjones5294]

@@jefftranter -- If you are still looking for one, I think I still have one, in my mini-warehouse. I built a lot of the demo items, at the Atlanta store. My very first Heathkit that I bought for myself, was an IM-25 VOM. I still have it, but the battery clips broke, and I was never able to find replacements. The Atlanta store, was an amazing place.

[@jafinch78]

Is this the same, in a Heathkit version packaging, as the Fluke 8020? I've read the Fluke Model 77 and others were marketed by Heathkit also.

[@jefftranter]

I haven't see a definitive answer on whether Heathkit worked with Fluke to offer an equivalent to the 8020 in kit form, or if they copied it. The plastic case is almost, but not identical to the Fluke, leading me to think that it was a Heathkit design based on the Fluke 8020.

[@jafinch78]

@@jefftranter Thanks for the feedback . From what I observe, Heathkit did a better job detailing information in regards to the calibration procedure. I don't have that in the 8022B I was given for free with a bleeding LCD. Would you happen to have a more accurate idea of the issue with the LCD screen bleeding as shown here: facebook.com/groups/147848912365070/permalink/544501289366495/ (see my comment reply under Dave Sheldon's post comment for image)

[@GrahamNicholson56]

I built the Heathkit IM-2215 and acquired the blue Fluke 8020 case for it in the belief that it would fit. It did, but very tightly in length suggesting that the Heathkit case was at least a few millimetres longer. Perhaps this was due to it being an approximate copy or perhaps Heathkit had to enlarge the Fluke pcb design to make it more suitable for kit assembly. Unfortunately I no longer have the meter as the LCD display faded over time. It did well to last over 35 years.

[@youtuuba]

I have done a details study and comparison between the Fluke 8020 and this Heathkit IM-2215. While Heath certainly was inspired to produce something comparable to the 8020, their design is their own and NOT a copy of the Fluke product. Between the 8020 and IM-2215: - They use different 'digital voltmeter ICs'. Fluke worked with Intersil to design and manufacture a proprietary single-chip voltmeter IC, then Intersil made a different IC (two sibling ICs), the 7106/7107 which had most of the same features and the special Fluke version, without being just a re-badged version. Heath used the '7106' in their IM-2215. The two ICs are not interchangeable, so the surrounding circuit design is necessarily different. - Form follows function. Both the proprietary Fluke IC and the Intersil 7106 ultimately do the same thing, and have similar dual differential inputs, which Fluke cleverly used to minimize parts count of the surrounding circuit. Although Heath was using a different IC than Fluke, it also has the same kind of inputs, leading Heath to ultimately design similar surrounding circuitry to perform the same functions. The circuits are similar but not the same. - Heath economized a bit there and there in places where Fluke did things a bit more 'professionally', but the specifications remain very comparable. Heath used less expensive, non-sealed switches compared to the ones Fluke used, and this probably explains why even to day a used 8020 still works nicely, while an IM-2215might be having issues with switch contact reliability. - The two meters do NOT use the same PCB design. The assertions by some people that Heath just put a Fluke 8020 PCB in a blue case are nonsense. - The whole way the battery and fuse are handled is different between the two. Also, Heathkit never produced anything based on the Fluke 77. This is easy to see with even the slightest research. Heath only produced two handheld digital DMMs, the IM-2215 and the IM-2230. The IM-2230 is even more distinctive from Fluke's handheld DMMs than the IM-2215 is, and they don't even look similar. There sure is a lot of guess work and pure BS on the web......