[ARC5] BC-454-A, etc. Selectivity option found?

[Kenneth G. Gordon]

On 22 Jan 2014 at 13:58, D. Platt wrote:

> As fortunes would have it, I discovered a long put away McMurdo Silver  
> model 805 100kHz IF amplifier, new in the box.  It purports to provide 
> added selectivity to "any receiver".  It taps on to the detector plate 
> and then feeds back into the audio gain pot.

Hmmm....sounds very much like a BC-453 with a mixer ahead of it.

Please keep us informed of its usefuless.

Ken W7EKB