I have weird thing going on with my HD 212. Let's start with what works.
Channel 2 no footswitch. Reverb and tremelo work as they should. When I use the footswitch the tremelo turns on and off and works as it should. When using the footswitch for reverb the reverb works as it should. When i toggle it off there is no sound unless volume is cranked to 10. Then it sounds like hi gain. I think this is because of the master volume setting. I looked at the schematic. It appears the foot switch for reverb is tied into the volume control of channel 2 somehow. Any thoughts?
Thanks
Fri, 06/02/2017 - 06:19
#1
Short
Hi Fred,
the foot switch for the reverb side is only tied to the reverb - the ch 2 volume is dual gang and feeds more signal to the reverb drive as the channel is turned up. The tremolo side of the foot switch is tied to the ch 2 volume since the tremolo is basically an oscillation of the ch 2 volume. What happens if you unplug the RCA plug to the foot switch from the black (tremolo) jack on the back? Does the reverb on-off behave normally then? If so, I bet there is a short in your foot switch somewhere. If the issue is the same, plug the red (reverb) RCA plug into the tremolo jack. If the foot switch is working as intended, the tremolo should now switch on and off with the reverb stomp button, in which case you may have a short inside the amp. My money is still on the foot switch somehow.
Cheers,
Lars Verholt
Reverb footswitch issue
Thanks. Removed the tremelo connection and it stilled did the same. I reversered both connections, still the same. When reversing the connections I unplugged the tremelo again ( which is now red) still the same issue. Buzzed out both switches on the footswitch and they both work. Mudt be internal. It appears from the schematic channel 2 volume is double stacked. 1 linear taper, the other audiob taper. Since this works fine without the footswitch. I wonder if the RCA jack is shorted. Ill check that next.
Thanks
Fred