Here's some update about this capacitance meter.
Since I have found no information about it yet, I've decided to do some basic reverse engineering, just for fun.
There's no CPU whatsoever. Just ADCs, lots of CMOS logic gates, counters, dividers, encoders, decoders, op-amps, and so on. Discrete electronics on its most.
I have learned that it uses two separate A/D converters, Teledyne TC8750 for Dissipation Factor (D) and Intersil ICL71C03 working together with an ICL8052 for capacitance (C).
Both A/D converters output data in BCD and requires BCD to 7-segment decoders and drivers.
Fortunately the datasheets of those are available on the web.
It's an overkill since they are not using all digits/counts these ADCs are capable of.
Attached is a close picture of the A/D section.
Notice the weird little brown resistors that look like capacitors. Never had seen any like these before.
All ICs are dated as 82, 83 and 84 so it probably has been built in 1984. Most of the logic ICs are from Motorola, made in Korea, but there're also some japanese Hitachi, Toshiba and Oki. The op-amps are from JRC.
Fortunately most of the trimmers are clearly labeled, although I had no need to touch them. This beast showed to be very accurate already.
I still intrigued by the data connectors on the back.
Due to the lots of buffers and optocouplers they seem to be output only. Probably BCD.
I'll post some more details and pictures later on.