haskellbob
- Apr 13, 2020
- 21
- Joined
- Apr 13, 2020
- Messages
- 21
The attached fragment of a circuit is for the preamplifier board of a Heathkit AR-15 receiver. The volume control potentiometer has a fourth terminal. I can see that it has something to do with the Loudness (bass-enhancement) control, which is either on or off. Something is bypassed when the control is in the "on" position, but I can't quite figure out the logic or the functioning of doing that.
Could someone explain? Also, I was planning to replace the 25k double-gang potentiometer, but the replacement only has the usual three connecting points. Is there a way I can do this substitution - preferably retaining the "loudness" control, but, if necessary, doing away with it?
Thank you for your help!
haskellbob
Could someone explain? Also, I was planning to replace the 25k double-gang potentiometer, but the replacement only has the usual three connecting points. Is there a way I can do this substitution - preferably retaining the "loudness" control, but, if necessary, doing away with it?
Thank you for your help!
haskellbob