UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - 'Beau Decca 131 projection receiver 1950'

FERNSEH · 13th Oct 2015, 3:43 pm

A simplified circuit diagram of the focus control system employed in the Decca 121 and 131. The later model 141 omits the stabiliser valve V19.
The focus coil serves as the loss element to supply the 268 volt HT supply to the earlier stages which demand a much lower voltage.
The focus control itself supplies the RF and IF amplifier valves V1,2,3 & 4.
It doesn't appear to a very nice circuit but in fact I'm told it works very well indeed.

DFWB.

13th Oct 2015, 3:43 pm	#19
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: 'Beau Decca 131 projection receiver 1950' A simplified circuit diagram of the focus control system employed in the Decca 121 and 131. The later model 141 omits the stabiliser valve V19. The focus coil serves as the loss element to supply the 268 volt HT supply to the earlier stages which demand a much lower voltage. The focus control itself supplies the RF and IF amplifier valves V1,2,3 & 4. It doesn't appear to a very nice circuit but in fact I'm told it works very well indeed. DFWB. Attached Thumbnails