This is Benmar Navigator 555 3 bands direction finding radio with variable gain and on RF receiver. Benmar 555 navigator was manufactured under contract for major companies like BENDIX and was equipped with NOAA WX band and adjustable BFO for SSB CW reception. This radio was able to be used to determine accidental interference from nearby power lines or intentional interference. Benmar 555 Navigator was able to provide 150 kHz-420kHz longwave and medium shortwave from 1.6Mhz-4.6MHz frequency coverage. It was a very nice audio sound in receiving amateur radio signal in the 75-80 meter band. Here is Benmar Navigator 555schematic diagram that consists of lamp switch, ammeter, IC 201, etc.
see Benmar Navigator 555schematic diagram here