Hello, I have just bought a used Fostex DMT-8VL and it has a dead Channel, I am trying to find some advice about what could be causing this?
I don't know anything about repairing multitrack recorders or mixers, I bought this item thinking I was buying a fully working digital multitrack but it turned out to have a few problems which I think after a closer look were caused by liquid at some point in its life, I noticed that all the faders were rough and giving inconsistent audio from the input channels, and channel 8 was giving no audio at all, I stripped the whole recorder down and gave it some TLC all the faders have been thoroughly cleaned channels 1 to 7 are perfect with consistent audio all the way up the faders and they slide nice and smoothly now, the only issue it still has is the silent Input Channel 8.
What I have tested so far
If I turn the levels to their limits I can just about hear the audio from input 8 but its very faint, if I switch the L/R-Mon switch to Monitor I can hear the audio signal coming in from the channel 8 jack and I can raise lower the volume and pan the signal left and right using the pots in the monitor section but the fader, eq and meters have no effect when in this mode so I suspect that the problem is after the Monitor section?
I used input 1 to send and record the audio signal to Input Channel 8 and the Channel 8 Led Meter responded to the signal and recorded the track but I can hear nothing on playback the fader does nothing to the signal yet the meter for track 8 is peaking away showing that there is a recording there?
The recorded output from track 8 cannot be heard from the stereo outputs but it can be heard loud and clear from the rear direct out for Channel 8 so I am assuming that the recorded track bypasses the channel 8 fader section altogether?.
So I am stuck without any schematics or previous knowledge on mixer repairs, I am hoping someone can put me on the right track so to speak?
Thanks in advance
Dale
I don't know anything about repairing multitrack recorders or mixers, I bought this item thinking I was buying a fully working digital multitrack but it turned out to have a few problems which I think after a closer look were caused by liquid at some point in its life, I noticed that all the faders were rough and giving inconsistent audio from the input channels, and channel 8 was giving no audio at all, I stripped the whole recorder down and gave it some TLC all the faders have been thoroughly cleaned channels 1 to 7 are perfect with consistent audio all the way up the faders and they slide nice and smoothly now, the only issue it still has is the silent Input Channel 8.
What I have tested so far
If I turn the levels to their limits I can just about hear the audio from input 8 but its very faint, if I switch the L/R-Mon switch to Monitor I can hear the audio signal coming in from the channel 8 jack and I can raise lower the volume and pan the signal left and right using the pots in the monitor section but the fader, eq and meters have no effect when in this mode so I suspect that the problem is after the Monitor section?
I used input 1 to send and record the audio signal to Input Channel 8 and the Channel 8 Led Meter responded to the signal and recorded the track but I can hear nothing on playback the fader does nothing to the signal yet the meter for track 8 is peaking away showing that there is a recording there?
The recorded output from track 8 cannot be heard from the stereo outputs but it can be heard loud and clear from the rear direct out for Channel 8 so I am assuming that the recorded track bypasses the channel 8 fader section altogether?.
So I am stuck without any schematics or previous knowledge on mixer repairs, I am hoping someone can put me on the right track so to speak?
Thanks in advance
Dale
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Welcome to diyAudio.
I think you will get a better response if you post in a different forum thread. Not everyone looks here into the intro section.
I think you will get a better response if you post in a different forum thread. Not everyone looks here into the intro section.
Thanks yes I put it into the PA Systems part of the form as well earlier today, hopefully that is the best place.