Tascam 388 quiet track issue

[safetyman]

Hello, I have had my tascam for many years with relatively few issues. Yesterday out of no where channel 6 started recording very quietly. While in "mic" the level and sound were fine but then upon playback the vu showed barely anything and signal and the playback as extremely quiet. So far i have reseated all my boards with no luck. I swapped boards, the problem still persists on channel 6.
I did have brief success when i took out board 6, recorded on track 6 (obviously with no playback results) then put board 6 back in and recorded again, perfect signal. A few minutes later i tried again and were back to quiet track. I have also messed with all the buttons and knobs while recording to see if it is a dirty pot somewhere and nothing. The only thing that showed and sort of results is when i tapped on the actual mixer around track 6 while recording. Each tap would give brief amplified signal.

I have also tapped on the relay of track 6 with a wooden stick while recoding to see if that would signify a bad one. No difference.

Any clue?

 

[sweetbeats]

Hi.

You said you “…tapped on the actual mixer around track 6…” you’re talking about input channel 6 when you say “track 6” right? I just want to make sure. I know sometimes people refer to mixer channels as tracks, but I think it’s helpful in this setting here to call tape tracks “tracks” and audio pathways “channels”. So you were tapping on the dress panel around input channel 6, right?

Try this: tip the 388 on its side and remove the bottom panel. There is a buss PCB that spans all the way across the mixer PCBs. My hunch is you have a bad solder joint on either the channel 6 input PCB, or on the buss PCB where it connects to the channel 6 input PCB. Or you need to exercise the connection. So look for a bad solder joint, and/or gently manipulate the buss PCB there where it connects to the channel 6 input PCB while recording and see if doing that makes anything happen.