[ARC5] "ARC-5" Receivers and "Q" multipliers

[Kenneth G. Gordon]

On 11 Aug 2015 at 1:52, WA5CAB at cs.com wrote:

> There was an article in QST probably around the summer of 1961 for a Command Set
> receiver Q-multiplier.  Used only a pot and a gimmick.  Worked pretty well. 
> Took some ingenuity to get the pot shoehorned into the plug-in front box,
> though.

I've used that one: it works fairly well in the 6 - 9.1 MHz receivers, not so well 
in the 3 - 6, and not worth doing in the MF jobs. What it actually does is to 
make the first IF regenerative. It works pretty well when the signals are weak, 
but as the signal levels rise, it gets less effective.

Even so, a REAL "Q" multiplier works a lot better.

Mike Murphy WU2D's addition of a crystal-filter to the 6 - 9.1 MHz jobs 
REALLY makes a huge difference. He simply uses the first IF coil and a 
crystal to do that.

Ken W7EKB