The RCI29 "10-meter" base radio is built into the same cabinet used for the Galaxy (RIP) DX2547 40-channel CB. Has the new circuit board used in the X9 and other models. This customer complained that the Tone knob didn't do anything. It's not strictly a "tone" control. Technically it's only a treble control. Cuts the high-end component of the receiver audio only. I could hear the slightest difference turning the Tone knob end-to-end, but barely. There is a 2-pin plug on the circuit board where the Tone control is mounted, but that's not important now. It has two wires, yellow and orange. I traced them to this 2-pin socket on the main circuit board. It has a "J" callout number on the far side, but I failed to make a note of it. The pin with the yellow wire is marked "TO" and the other one "GA".
I cut the yellow wire, the 'hot' side of the Tone control. The orange wire is ground and gets left alone.
The yellow wire gets lap-soldered to one end of a .022uf (223) ceramic capacitor. I'm sure a green plastic-film cap would be equally suitable.
This connector site marked J39 is unused in this model, but the two rear-most pin pads are marked "AF IP" and "AF OP". They are tied together with a zero-ohm smt "resistor", so you can use either one to terminate the free end of the .022 cap.
This places the series combination of the new cap and the Tone pot in parallel with the audio feeding into the volume control.
Made a big difference. YMMV.
73
I cut the yellow wire, the 'hot' side of the Tone control. The orange wire is ground and gets left alone.
The yellow wire gets lap-soldered to one end of a .022uf (223) ceramic capacitor. I'm sure a green plastic-film cap would be equally suitable.
This connector site marked J39 is unused in this model, but the two rear-most pin pads are marked "AF IP" and "AF OP". They are tied together with a zero-ohm smt "resistor", so you can use either one to terminate the free end of the .022 cap.
This places the series combination of the new cap and the Tone pot in parallel with the audio feeding into the volume control.
Made a big difference. YMMV.
73
