Micronta FET meter28 range electronic multimeter model 22-208. The circuit incorporates two field effect transistors and has an input resistance 10 megohms on DC voltage ranges. It requires one 1.5 volt type c cell and one 9 volt PP3 type battery. Working, Korea and Japan, date 1968/9.
This is one of several instruments given to me by Deborah Waters, which belonged to her late father. It has required no attention other than cleaning, lubricating the switch mechanisms and inserting batteries.
Interior of the instrument [note printed circuit switch]
box [inside printed USA ]
SPECIFICATIONS
Range
DC Voltage------------------0-0.3-1-3-10-30-100-300-1000V
AC Voltage------------------0-3-30-100-300-1000V
DC Current------------------0-100uA -3mA-30mA-300mA-10A
Resistance------------------0-1K-10K-1Meg-10Meg-1000Meg (centre scale
10)
Decibels---------------------20 to +62dB in 5 ranges
Accuracy
DC Voltage------------------3% of full-scale
AC Voltage------------------4% of full-scale
DC Current------------------3% of full-scale
Resistance------------------3% of scale length
Sensitivity
DC Voltage------------------10 megohm [on 1000V range is 32 megohms]
AC Voltage------------------10Kohm/Volt
DC Current------------------315 mV
Frequency Response-------30Hz to 200 kHz at 3, 10 V Range
Meter Movement: 5", 3-colour, mirrored scale, 25uA movement
Battery: Requires one type "C" battery and one 9-volt rectangular type
Micronta is a trade name for instruments made for Radio Shack, a Division of the Tandy Corporation of Fort Worth, Texas, USA and Barrie,Ontario, Canada
