TEAC Reel to Reel 3340S

[Gtown]

Need some help. Was recording on my TEAC 3340S and hit 'Stop' to select a new song from the CD player. When I went back to push Record/Play, nothing happened. None of the switches are doing anything (Fast Forward/Rewind/ Start Record, Play). The unit powers up and off, VU meters light up. It is properly laced up and tension arm is working. Capstone motor working and spinning, pinch roller has been working fine and don't believe that is the issue. Tape reel is half way thru, so tension is still on the tension arm. The issue appears to be all 6 control switches. Any ideas or suggestions? Thanks!

 

[dankik]

Hi, do you understand schematics and circuit logic diagrams?
Here is a page from the whitepaper "The Teac A3440" by Les Carpenter (A look into the circuitry of the Teac A3440)
Maybe the power-on reset is not working.

 

[tadawson]

Check power suppies! It would not surprise me if there was a different source for transport logic (solenoid drice and such) that was separate from that for audio (isolate from inductive glitches from solenoids and such), which may have died.

 

[Gtown]

Hi, do you understand schematics and circuit logic diagrams?
Here is a page from the whitepaper "The Teac A3440" by Les Carpenter (A look into the circuitry of the Teac A3440)
Maybe the power-on reset is not working.

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Thank you!

 

[Tonoje]

One fairly easy check/fix you can try is to ensure that the cam on the rear of the tension arm is activating both microswitches. One is mounted right "behind" the other, which may not be obvious at first glance.

 

[rojoknox]

Greetings from RojoLand!

@Gtown — Please note that 'dankik' gave you information for the Teac A-3440, which is very different from your 3340S (other than both decks are four-channel machines). A manual for A-3340S (same thing) can be found online.

Take care,
—
J. E. Knox "The Victor Freak"

 

[TurboSound]

Like Tonege said, check the micro switches to the left of the pinch roller arm. These are labeled "Safety switches" on the schematic. Also there are 2 more micro switches (S10 & S11) in series with the Capstan and Brake solenoids. These are mounted to the take-up reel brake solenoid. Both S10 & S11 should be closed when the Brake solenoid is not energized. I was just in this circuit for my 3340S with a similar problem.

The 3340S is similar to the A3340S but not exactly the same. You can use the A3340S Service doc's and schematics but know that some of the wiring is different.

 

[Gtown]

It was the two microswitches next to the pinch roller. They have been replaced and works like a charm!