TEAC A-3340S RECORD RELAY and RELAY CONTROL BOARD
This has been another tape deck nightmare... I always seem to come out of the woods at the end, but when I'm sent out looking, it's pretty bad!
This Teac thing!!! UGH!!!
The one thing I can't figure out is the relay control that attaches to the buttons on the front has a transistor that is shown in the schematic diagram of the PCB as in a totally different place! The PCB is seeming to be the problem, but on this thing I've been down many rabbit holes and came out scratching my head... just glad that I didn't LOSE any functionality for my troubles.
It seems like the K1 relay is not being energized... You can put it into record mode, the lights light up on the individual channels. you can start recording, but it only erases... and it erases rather poorly. If I check the bias amp boards, the main relays are triggered, but the secondary relays aren't... and if I really bury the levels I can even hear a whisper of the signal being recorded (I realize this isn't something i should do often)
Are the secondary relays on those cards for recording. the individual channel ones, triggered by AC instead of DC? Because I can get an AC voltage change if I actively switch them while in recording mode, they just don't move... any of them... and that seems too unlikely, unless they are known for all FUSing together... but I haven't read that.
And curious if the Transistor (d235) is correct? It seems there were a few changes done to this board after the schematic was made... and that makes things all the more difficult in this mess of a machine (with all due respect, I like these machines!) I just can't get this done and i REALLY WANT TO! lol It's so close and I've fixed SO much on this thing... I hate having it all apart and there's so little info in the manuals and the schematics which are outdated apparently before these were even produced.
I have this feeling that maybe it's a matter of voltage not being where it should be, but they don't make the voltages known on any of these... like all of these many many many places you could check... no chance! And someone had to have that info... if there are any voltages and checks i can do at the power supply... OR maybe that VARIABLE resistor that I can't seem to find any reference to in the one power supply... where is the REAL manual?? LOL
I did a lot of testing... and I put some leads on the relay control board, where k1 is located.... and engaged RECORD/pause and the coil for k1 seemed to get energized a little and then fizzled down to nothing... I changed caps, and even some diodes along the way. I even changed D235, because I had that and I didn't realize the schematic and REALITY were divergent... so forgive my installing them on the top of the board... that would have taken a LOT longer to put in the bottom... included a few pics and can send more. I'd like to have this out there, because someone is going to run into this issue, I have a feeling... or already is.
thanks for any help!
This has been another tape deck nightmare... I always seem to come out of the woods at the end, but when I'm sent out looking, it's pretty bad!
This Teac thing!!! UGH!!!
The one thing I can't figure out is the relay control that attaches to the buttons on the front has a transistor that is shown in the schematic diagram of the PCB as in a totally different place! The PCB is seeming to be the problem, but on this thing I've been down many rabbit holes and came out scratching my head... just glad that I didn't LOSE any functionality for my troubles.
It seems like the K1 relay is not being energized... You can put it into record mode, the lights light up on the individual channels. you can start recording, but it only erases... and it erases rather poorly. If I check the bias amp boards, the main relays are triggered, but the secondary relays aren't... and if I really bury the levels I can even hear a whisper of the signal being recorded (I realize this isn't something i should do often)
Are the secondary relays on those cards for recording. the individual channel ones, triggered by AC instead of DC? Because I can get an AC voltage change if I actively switch them while in recording mode, they just don't move... any of them... and that seems too unlikely, unless they are known for all FUSing together... but I haven't read that.
And curious if the Transistor (d235) is correct? It seems there were a few changes done to this board after the schematic was made... and that makes things all the more difficult in this mess of a machine (with all due respect, I like these machines!) I just can't get this done and i REALLY WANT TO! lol It's so close and I've fixed SO much on this thing... I hate having it all apart and there's so little info in the manuals and the schematics which are outdated apparently before these were even produced.
I have this feeling that maybe it's a matter of voltage not being where it should be, but they don't make the voltages known on any of these... like all of these many many many places you could check... no chance! And someone had to have that info... if there are any voltages and checks i can do at the power supply... OR maybe that VARIABLE resistor that I can't seem to find any reference to in the one power supply... where is the REAL manual?? LOL
I did a lot of testing... and I put some leads on the relay control board, where k1 is located.... and engaged RECORD/pause and the coil for k1 seemed to get energized a little and then fizzled down to nothing... I changed caps, and even some diodes along the way. I even changed D235, because I had that and I didn't realize the schematic and REALITY were divergent... so forgive my installing them on the top of the board... that would have taken a LOT longer to put in the bottom... included a few pics and can send more. I'd like to have this out there, because someone is going to run into this issue, I have a feeling... or already is.
thanks for any help!
