For sale is a vintage mono amplifier. Has selector for phono, dynamic or crystal microphones. I’m guessing this may have been used for ham radio or broadcasting. It’s definitely homemade. Uses (2) 5881 tubes and (4) 12AU7. I have not tested this unit because it has one end of a cap on an input that’s not hooked up to anything and one loose wire on the volume pot. This has high quality transformers. The power supply transformer is Freed which was used on very high expensive broadcast gear back in the day. The output transformer looks to be an earlier Altec/peerless. Sold as is for parts or repair only. I will ship with great care.