I purchased an item at an estate sale that is made by CVP Products (printed on circuit board), it has the # HRN-1 on the circuit board. It's a metal box aprox 9 in wide X 5 in deep X 1 1/2 in H. The front has 5 dpdt switches (probably 3 -4 $ switches) with center off, push button circuit breaker, a volume control (pot) and an off and on switch. The back has two RCA jacks and a circuit breaker for the ac line cord. There are no markings on the enclosure other than numbers on the 5 dpdt switches.
I think it's related to the RR hobby as there was some other RR items at the sale but am not sure. Thought maybe I should find out what it is before I start salvaging it for parts that I could use. Rob Mills ~ Tulsa
PS, Circuit board has 4 IC's and 4 transistors. Transformer is 6.3 volts either side of center tap.