[ARC5] Potentiometer value needed

[Kenneth G. Gordon]

On 9 Aug 2014 at 14:21, Jim Falls wrote:

> I have a lightly hacked (12 filament mod) silver BC-453-B with an on/off switch,
> volume control and phone jacks in the front cubby hole. Current pot is far to
> touchy and probably linear taper. What's a good value audio taper to use for
> hi-Z phones/speakers? I'd like to try it with my TCS and others. 

Hi, Jim:

That "gain control" is a combination RF/IF gain pot acting on the cathodes. I 
have found that a 50K log (audio) taper pot works well there.

Since you are, apparently, going to use that BC-453 as a "Q-5er" for your 
TCS receiver, I suggest that you add an AF gain control to it.

Use a 2 megohm (or a 1 meg) log-taper pot to replace R-20, the 12A6 grid 
resistor, then connect the wire that attaches to the 12A6 grid connection 
which comes from the flat .006 mfd capacitor to the pot wiper.

Ken W7EKB