3
3nsdan
New member
I really screwed up somehow. I have a rebel 30 head, bought used about 6 months ago.
Since i don't know much about the history of this particular amp, I decided to re-tube it. I put all new preamp and power tube in. When I went to check the bias, I got no reading at the test points. I also plugged into the input and confirmed there was no sound. I put all the old tubes back in, one group at a time, and tested for bias reading and sound output each time. Even with all the original tubes, nothing. I checked the fuse in the back, and it's good. I started thinking that maybe something came undone on the PCB when I had removed the amp from the head chassis.
I tugged on each unpluggable lead I could to make sure they were tight. Sure enough, I found to leads unplugged! They were dangling near 2 connections marked QC11 and QC12. I was so relieved! I plugged them in, fired the amp back up, but still no sound. Uhhhggg! I started to realize that I didn't actually know which plug went on to which connector.
I reversed them, but same outcome. There is no voltage at the bias test points, the output transformer is cold, and no sound. That seems like signal isn't flowing into the power section... I feel like it HAS to be related to those QC11 and 12 plugs, or something nearby.
Now I'm totally distraught because I just ordered an Avatar cab, and now my heads dead! Can anyone think of something that i hopefully missed? Or could I have damaged the amp by messing with those 2 pcb plugs?
Thanks for any advice
Dan
Since i don't know much about the history of this particular amp, I decided to re-tube it. I put all new preamp and power tube in. When I went to check the bias, I got no reading at the test points. I also plugged into the input and confirmed there was no sound. I put all the old tubes back in, one group at a time, and tested for bias reading and sound output each time. Even with all the original tubes, nothing. I checked the fuse in the back, and it's good. I started thinking that maybe something came undone on the PCB when I had removed the amp from the head chassis.
I tugged on each unpluggable lead I could to make sure they were tight. Sure enough, I found to leads unplugged! They were dangling near 2 connections marked QC11 and QC12. I was so relieved! I plugged them in, fired the amp back up, but still no sound. Uhhhggg! I started to realize that I didn't actually know which plug went on to which connector.
I reversed them, but same outcome. There is no voltage at the bias test points, the output transformer is cold, and no sound. That seems like signal isn't flowing into the power section... I feel like it HAS to be related to those QC11 and 12 plugs, or something nearby.
Now I'm totally distraught because I just ordered an Avatar cab, and now my heads dead! Can anyone think of something that i hopefully missed? Or could I have damaged the amp by messing with those 2 pcb plugs?
Thanks for any advice
Dan
