This reflectometer or standing-wave ratio meter (SWR) was found in a 1980s American documentation. The diodes support general purpose equivalents.
This circuit fires by burning the fuse when the input voltage exceeds the value referenced by the zener....
The UAA180 integrated circuit is no longer manufactured, but if the reader finds one in a scrap...
We find this circuit in a Radio Electronics of July 1984. It consists of the traditional version of 1 A...