BITX40 Low audio volume with 8.5V to board/Raduino

Steve
 

Hi gang.  So I thought I'd get stupid and add complexity where none is needed.  Radio: BTX40, 1.27.7 'ware, basic hardware mods.  I put a buck converter between the power switch and the leads that feed B+ to the board and the Raduino- thinking I'll save some power, or be easier on those parts, temp-wise- and adjusted the voltage to 8.5.  Now, the previously robust speaker output is much diminished, and the volume control has no effect after about half it's initial rotational travel.  If I adjust the B/C up to maximum- 11.7V- still low volume. If I de-fuse the B/C and jumper around it (note that the led on the b/c lights up when I do this) and use the bench power supply to reduce the V in to 8.5V, the audio is a bit lower than with 13.8V, but the volume control functions as normal.  Note that the radio and all the wiring is still spread out over the bench....Removing the B/C is the easy solution, but I'm just wondering.....Aloha, Steve WH6ST

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