Roberts Valve RMB


This is a nice valve portable set. Mains or battery operation. It dates from around mid 1950s and uses the new range of “D” low power valves, having 1,5V heaters and an HT supply of 90V. DK96, DF96, DAF96 and a DL96 pentode for the output, giving a stonking 200mw of HiFi power! The earlier models, in the same sort of case were based on a traditional mains radio layout with larger hotter octal valve line up. When I got this set, apart from the leather handle having fallen to bits, the condition was great. Powered it up expecting a working set. Totally dead. Had a quick check around and saw we had 90V at one end of the output transformer, proving the inbuilt mains power supply was working. However, on the anode connection of the output transformer, no angry pixies could be found? I stared at the output transformer and willed the primary winding not to be open circuit. My will was not strong enough. Look, the transformer does not have a hard life does it? It sits there even at full volume doing 2/3rds of sweet nothing, so what with the open circuit winding? Off to the box marked output transformers and managed to find something was would be a near enough match. A quick check around and the capdensors all seemed to be in good order for once. Power up and joy of joys. Good sound, very selective and even the Short Wave pulled in a few stations.  Not the most pretty of looking wireless sets but I guess it represented the post war austerity feel.

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