USSR frequency meter Ch3-57 - brief overview, description of controls, inspection of documentation.
The electronic frequency meter Ch3-57 is relatively little represented in reviews, but it is a rather interesting device of the 20th century. The Soviet device Ch3-57 is assembled on microcircuits of the K133, K100 and K155 series, i.e. does not contain nodes, LSI and microcontrollers. Only chips with a small degree of TTL and ESL integration. It has no parameters exceptional by modern standards, but for its time it was a good device.