Play back problem on a Teac 2300

[brian3591douglass]

I'm a new be to this site, I'm a new be to all sites. I have just got back into my old analog equipment. I have a couple Teac 2300sd's that have new problems to me. One all of a sudden has a garbled play back in both channels but using head phones its crystal clear. I have checked the leads, cleaned the heads and still no change. I did check the receiver and it does work with the other 2300sd. Any suggestions on what direction to look would be greatly appreciated

 

[anatech]

Hi Brian,
It's been years since I worked on one of those! Normally I would think that your record switch could use a cleaning, but it's clean into headphones. Interesting that it involves both channels. Does that model have separate level controls for line output and headphone output? If so, try cleaning the line out controls. Use very little cleaning solution. Try not to spray it, rather see if you can have the cleaner come out slowly.

If you can't figure it out, it looks like an interesting repair. I still service those, but only electronic faults since I lost my test tapes.

-Chris

 

[brian3591douglass]

Thank for your suggestions, the heads, pots, and all switches have been cleaned

 

[Chris Daly]

Could be the monitor switch is ON which if I recall are small front panel toggle switches, switching them UP should then give the tape output rather than what you are monitoring from the inputs , and infers headphones are wired before the outputs.

 

[anatech]

Hi Brian,
If Chris' suggestion doesn't pan out, I'm afraid it's broken and needs more in depth repair. It's possible that a muting circuit is misbehaving. It looks like it is schematic time. Can you post a clear picture of the front panel? I looked through the Google images without any luck.

Just a thought. The logic on these older machines tends to be relay types and they may have used a relay for the mute function. I would expect the headphones to come off later in the circuit, but it may be possible that you are looking at dirty relay contacts. Its one of those things that I'll remember more clearly if one was on the bench.

-Chris

 

[PRR]

Service manual--
TEAC A-2300S - Manual - Stereo Reel to Reel Tape Recorder - HiFi Engine

I once maintained these things for a salary. Not fond memories. The machines were OK, there were other factors....

My un-fond memories were correct. The headphone amp comes RIGHT off the line output wire. And there is no muting.

Is it possible the amplifier the line out goes TO is "garbling"?

It is also possible (even likely) that C210 is leaking DC. This may upset an otherwise healthy external amp, but the internal headphone amp has another blocking cap.

 

[MAAC0]

Interesting... The Headphone out is isolated by a transformer... Try to tap before the transformer C212 or 213 to see if You can get a clean signal, but put a 1K limiting resistor or pot in series.

 

[anatech]

Hi PRR,
Yes, from that circuit, C210 could be leaking. Since he has this issue with both channels, it might just be time for many electrolytic capacitors to be changed.

I once maintained these things for a salary. Not fond memories. The machines were OK, there were other factors....

I worked on the entire line. Not a bad machine compared to other brands I've worked on. They also suffer from "green grease syndrome", so its best to strip them down, clean and relubricate things. When the grease gets really bad, it becomes solid and there is a chance that the machine is lost.

-Chris

 

[brian3591douglass]

I seem to have all the things mentioned above. The green grease and all, I had this all apart and cleaned it every where. I freed up the pinch roller and the tensor arms, one was real slow moving. Cleaned all the pots and switches, put it all back together and it worked great. Then decided I should have oiled the motors, so back in I went. I found a syringe that fit the tiny tubs perfectly and proceeded to oil way to much though, from a video I watched on you tube, it said when the oil stopped going down the tube your finished. I ran the motors they seemed fine. I let it sit over night and a couple days later when to use it, just garble. I'm hopping Chris is correct that cleaning he switches will be a fix, he sent me in the right direction, all the switches are oily. So I will clean these all up tonight. I have a second machine exact same but it has no record since I got it. I did the exact same thing to it at the same time, and it remains the same no recording. I will post a couple pics latter tonight. I hope cleaning up the switches on both will be the fix for both. I'm very green when it comes to working on these reels, but I love to work on Thorens tt I have to many of then, but they at like pets that I cant part with them. I have chosen the kid's to receive them one day same as the reels. Thanks to all the responders how are helping me. It is greatly appreciated !!


Thanks Brian

 

[brian3591douglass]

Chris I have cleaned the left and right monitor switches and now there is no sound at all. what do you think both the switches are shoot, in source the meters show no activity but in tape, the meters work and clear sound on head phones. To me it appears that all the toggle switches must be disconnected by two screws on each switch, to move the circuit board apart to expose toggle body's. Do you think replacing both toggles will fix problem. And my other machine with no record function, do you think the toggles for left and right record, on and off, may remedy that problem. I'm in real deep water with the tear down that I have done. I have learned a lot about these, in the last couple days. But I'm sure the replacement of these will be a memorable experience.


Thanks Brian