Roberts Transistor Radio model RM30


Roberts RM30 mains LW, MW and VHF (88-102 MHz) radio. First made in 1978 and continued in production until 1980. at the time it would have cost between 62 and 70.

I purchased this set even though it had a fault (it only played quietly and the volume control was ineffective)because it had all the aluminium covers.

The resistance track and the connections of the volume control are printed on to a small square of insulating material. The output was low and invariable because the wiper had scored and broken the connection to the wiper. An effective although time consuming repair was made using a brass washer and a short length of wire, see diagram.

As can be seen from the following photograph this involved drilling out the rivets and splitting the switch mechanism away from the potentiometer. I assembled it incorrectly the first time and had to take it all apart again and reassemble the two parts. I glued the Bakelite potentiometer track to the metal moulding and fixed this to the switch using copper wires.