[ARC5] BC-455 adventure

[Kenneth G. Gordon]

On 16 Jun 2012 at 15:28, Bill Fuqua wrote:

>   I had good results doing this as well.
> I added a gimic capacitor from plate to grid of the IF amplifier, took
> that stage off the AVC line and added a pot in the cathode to make it
> function as a Q-multiplier. That worked rather well. You could reduce
> the pot until it oscillated and back off  and achieve very good CW
> selectivity.
> 
> 73
> Bill wa4lav

I did that too. I used two pieces of #12 insulated house wiring, about 3/4 inch 
long, soldered side-by-side to the grid and plate terminals at the socket, and 
used a pot in the cathode.

It works very well for weaker signals, but as the signals get stronger, the 
selectivity "automatically" widens out.

Even so, it was a very worthwhile addition to the 40 meter ARC-5 receivers. 
They are (purposely) very broad.

Ken W7EKB