UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - R209

Keith · 17th Nov 2017, 7:47 pm

Thanks for all the replies:

Andrew2 - Yes it is basic injection into the last IF. No AGC in CW mode - the "Volume" control becomes a manual RF/IF gain control.

Don - Mine is also a MkII. I'd be interested in how yours performs on SSB.

G6Tanuki - Yes, it took me a while to figure out the gain control rationale. Then I realised that the bog standard method of lifting up the cathodes won't work - cos there aren't any! The valve tests OK but its anode feed had drifted up from 33K to over 50K. Replacing that helped a bit. I shall have a look at the decouplers.

Keith

17th Nov 2017, 7:47 pm	#5
Keith Heptode Join Date: Jan 2003 Location: Tewkesbury, Gloucestershire, UK. Posts: 693	Re: R209 - BFO injection Thanks for all the replies: Andrew2 - Yes it is basic injection into the last IF. No AGC in CW mode - the "Volume" control becomes a manual RF/IF gain control. Don - Mine is also a MkII. I'd be interested in how yours performs on SSB. G6Tanuki - Yes, it took me a while to figure out the gain control rationale. Then I realised that the bog standard method of lifting up the cathodes won't work - cos there aren't any! The valve tests OK but its anode feed had drifted up from 33K to over 50K. Replacing that helped a bit. I shall have a look at the decouplers. Keith __________________ Keith Yates - G3XGW VMARS & BVWS member http://www.tibblestone.com/oldradios/Old_Radios.htm