KIKUSUI-107C FET VOLT-OHM-METER This is a nice Japanese Volt-Ohm-Meter that I bought in 1999, in the same place I bought the AG-203. I paid R$15 for it at that time, something about USD10 today. In fact I bought two units. One I gave to a friend. Both were non-working, but the problem seemed to be easy to solve - just seemed. Some resistors of the input dividing network were burnt. No idea what values they were.  After asking Kikusui if I could purchase, or if they could send me a copy of the 107C manuals (with or without expenses), they answered: "Sorry, but Kikusui has no longer assistance for this equipment." :(

    I gave to my 107C an electrostatic painting and replaced the battery holder, also I dismantled the entire inner chassis and made a zinc surface treatment. It really looked like new. I place a contact transparent adhesive over the front plate to protect it against wearing the scale. Also I replaced the old connector for a BNC type, that is more reliable. 107C scale is very smart, clean and functional, with P-P indications and dBm scale. The only miss point is that they didn't provided an mid scale, with zero at the center. Since you can adjust the zero start point, you could have an automatic signal indication (the model 123B has a led to indicate negative DC voltages, automatic polarity selection). The scale also provides a TTL-L and TTL-H indications.

    After years searching, in early 2005 I found in the old equipment archives at my job the specifications for a Kikusui made Volt-Ohm-Meter called 123B. I borrowed the specs and compared to the 107C. Despite of some differences, the DC input circuit had the same principle, with 10MW total input impedance. The DC input resistor attenuator network of 123B uses 2.16kW and 6.84kW multiples, and the 107C uses 233W and 66.7W multiples. See fig below:

    After replacing the 233R and the 66.7R, the unit came back to life.

    I like the 107C for bench work and it is very useful because of the 1500V scale. I really like this rig.

Approximate specifications:

DC Volts measurement:

AC Volts Measurement (sinusoidal):

Ohms Measurement:


    I asked to my friend, to give back the other 107C, I will restore it and give it back to him. But maybe some day he remember to do it......