Sunbeam U35

Sunbeam radio were one of the small manufacturers that sprang up in the early 1930s to exploit the burgeoning new market in wireless. They had premises in Acton, London NW10, but the company only achieved a tiny market penetration and had ceased trading within a few years. Sunbeam made several different models, the construction of which seems to suggest that they believed they had a secure future. For example instead of using generic components, many chassis parts had custom made pressings to include the company name Sunbeam, (for instance the coil cans etc). Sunbeam seems to have tried to establish a market niche by specialising in the manufacture of AC/DC receivers. There are very few Sunbeam radios still surviving, in fact I only know of model 22 and 57 from 1934, and the example shown on this page - the model U35 from 1933. All the aforementioned radios can be operated on AC or DC mains without any alteration to the receiver itself, a selling point offered by very few other manufacturers. 

This radio is particularly unusual in that it uses a valve line-up that appears not to have been used by any other U.K. production radio (unless you know different - in which case please email me). The valves were made by Tungsram, and were known as the "2018" series. This series of valves featured 20v heaters (except rectifier at 30v) and drew 0.18A. Even more unexpectedly these valves were made in Hungary. In the early 1930s the BVA (British Valve Association) required manufacturers to use valves made within the U.K. It is not known how Sunbeam managed to circumvent this ruling, one can only presume that they were such a tiny company that either nobody at the BVA noticed, or they were too small to bother with. That said this is the only company I am aware of that seems to have escaped the attention of the BVA. It appears that Sunbeam was the only company to utilise the "2018" series of valves in it's radios. Therefore it is not surprising that obtaining spare valves was very difficult, thereby making them difficult to repair at a cost effective price, and no doubt contributing to the early demise of the few radios that were made. The radio shown is working, and the performance is reasonable for a TRF receiver. When operated from AC mains the V2118 operates as a half wave rectifier. On DC mains the valve heaters will drop much of the mains voltage, the rest is dissipated by use of a filament resistance bolted to the chassis. Although the chassis is being used as a substantial heat sink, there is still an alarming amount of heat generated by the filament resistance. 

The cabinet is typical of 1933, and is nicely made in solid wood, except for the front panel that is veneered ply. All the knobs are definitely original, though it can be seen that dual speed concentric tuning knobs are used, which are different to the other three. The set sold for 9.9.0 and featured a valve line-up of V2118, SE2018, R2018, PP2018.

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