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TEAC A3300-10 - Takeup Reel Stopped Working

Discussion in 'Tape' started by Numone, Sep 4, 2018.

  1. Numone

    Numone Member

    Messages:
    90
    Hi all,
    I apologise in advance that I have posted this issue on another forum, and so far there has been one helpful response but nothing to the additional questions I've asked. There was a discussion on the lack of the existence of the model in question and that the "A" designation TEAC used on all their models meant those units were destined for "America". <sigh>...
    Anyway.... moving on....
    Yesterday, I replaced the felt brake pads on our '72 TEAC A-3300-10. Whilst going through the FF/REW/STOP/PAUSE/PLAY during the brake adjustment process everything was OK and finally the brakes were sorted. Then on pressing stop and moving the sliding switch to play and hitting the button, the capstan snapped-in and and then the deck stopped, because the take up reel wasn't turning, so the tape dropped the shutoff arm. Tried again and nothing. I rechecked the brakes to insure they weren't binding and they were fine. I removed the reels and NABS, and tried again.
    I noticed the takeup reel table was just turning a little CCW when I hit Play, so a small amount of power was getting through to the motor. I cleaned the sliding switch with Servisol Super 10 and after that, I did get it to work .... just once, but as I continued to try again, I heard clear electrical sparking from that switch, so I decided it was time to pull the plug - literally! I also checked the ceramic reel resistors and those too are fine. The one suggestion I did get "over there" was that the sliding Fast/Pause/Play switch has failed. Disappointingly, no one has answered my follow up questions. So, does anyone here think that's the probable cause, have any ideas on how to fix it or have any other ideas what the cause/s of this may be?

    All help, ideas and comments will all be much appreciated.
     

     

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  2. audiojones

    audiojones Jonesin' for audio Subscriber

    Messages:
    7,136
    Location:
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    Yes, that’s most likely what the problem is. I’ve run into this exact same problem with an A-3340 (the older version with the slider switch) and it was caused by the little fingers for the drum switch spreading out and losing contact with the wafer (that’s the arcing sound you’re hearing). It’s very difficult to get to but once you get to the drum switch you can carefully tighten up the contact finger so it will connect with the wafer again. Must be extremely careful as the wiring is very brittle and connections can snap off. FWIW (and apologies if you already know this) try not to ever use that switch for anything but mode change, in other words always hit Stop and then change direction or mode, never stop the machine by shifting the lever if you can avoid it.

    Also FWIW I’ve seen A series decks with universal voltage meant for overseas use and I’ve seen (and own) non A designated decks which are hard wired for 120 volt 60 cycle use so that whole argument is kinda out the window anyway.
     
    Numone likes this.
  3. Numone

    Numone Member

    Messages:
    90
    Wow, thank you very much audiojones for the reply; it's fantastic news to hear there is a "fix"!
    Can I ask you for some further help from you please, if possible, to give me a bit more info on how to..
    1. access the drum switch
    2. identify the fingers
    3. how you tighten them up and
    4. what to use to do this?
    I'm sure we're not alone in having this issue with these 47 year old decks, so this would be a great opportunity to get the fix out there for everyone who may have the problem in future.
    Yep, I know about the issue with using the leaver to change the current function, like stopping FF/REW by moving the drum switch to Pause; I honestly can't say I've never done this though!
    The "A" prefix designation was used globally, including in Japan, from the early 70's and not just on tape decks either; I have an AS and AT 200S amp and tuner.
    Thanks once again AJ and look forward to hearing from you again.
    Cheers... Rob
     
    Last edited: Sep 5, 2018
  4. audiojones

    audiojones Jonesin' for audio Subscriber

    Messages:
    7,136
    Location:
    Central NJ
    Well I'm not gonna lie, it's a very daunting task even for someone who works on them every day, so know your limits before you get in too deep. Not to sound conceited but honestly this one's not for a beginner. The switch is extremely hard to get to but if you have good mechanical skills, lots of patience, are very careful and can take your time you should be able to just barely access the contact fingers and the wafer assembly. As I recall (and I may have to ask the fellow AK’er that I helped out with this last year for some memory assistance) it went like this:

    Remove all of the knobs, shift lever bezel and lower faceplate.
    Remove the knurled nuts and washers for all of the control shafts and jacks (label where all of the jacks go first) and remove the inner lower faceplate panel.
    Remove the power switch, the record switch and the control button assembly and bracket
    Remove the screws holding the drum switch in place and remove the back of the machine as well as the right side panel.
    Carefully cut all of the wire tie tubing holding the wiring harness leading to the drum switch, but be very careful not to cut through any of the wires themselves.
    I seem to recall that one of the circuit board assemblies under the deck had to be removed (can't remember if it was the oscillator board or one of the amp boards) but again this was on a four track deck rather than a regular stereo deck.
    You should now be able to just barely free up the drum switch.

    Shift the drum switch to the play position and observe which contacts are being made, examine them all closely and look for the one that's all burned and discolored, that's the one that is arcing and causing the take up motor to drop out. If you shift the drum switch so the wafer isn't contacting the fingers (should be an open spot where the in the wafer where the contacts close together) you can very tactfully and carefully close the gap between them just a little bit (not too much or they will get mangled when the wafer travels back, they have to be able to spread when it moves into place). I used a very small screwdriver to give them just the slightest bend inward but again you've got to be very careful here and make sure they are aligned with the wafer before turning the drum switch or the contacts can get mangled.
    In our case we were able to do a live electrical test to locate the bad connection but I won't get into that here because it's a dangerous procedure and I wouldn't recommend it if you aren't experienced in this type of repair.

    Once the finger has been cleaned up (I like to use a fiber pen for contact cleaning) it's a matter of reassembling the whole thing. This is a major task so if you decide you can do it take lots of close up pictures before and during disassembly. Mark where everything goes before you remove them, once the faceplate and substructure is removed everything is hanging free and can go back together many different ways.

    Not an easy job, basically the drum switch was installed and the rest of the deck was built around it. Definitely look before you leap!
     
  5. Numone

    Numone Member

    Messages:
    90
    Thank you so much for the really comprehensive reply. As you say AJ, it certainly is a very daunting task, so I'm going to check with my very respected R2R technician who very local to me and check if he's handled this fix before... and get him to do it anyway! Thank you so much once again AJ - brilliant!
     
    Last edited: Sep 6, 2018
  6. audiojones

    audiojones Jonesin' for audio Subscriber

    Messages:
    7,136
    Location:
    Central NJ
    You’re welcome and good luck with it! These are great tape decks but it was a major improvement when TEAC changed them over to the button and relay operated design.
     

     

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  7. Numone

    Numone Member

    Messages:
    90
    Yes, they are.
    I paid £20 for this as a non-working unit a few years ago for the reel tables alone, after being told they'd fit our A7030 which, of course, they didn't so it went into the basement. I just plugged it in on the off chance a year or so ago and found it actually worked. After having it looked at by the tech at his suggestion earlier this year - he said there's no point chucking good money after bad - and confirming it was worth the effort, I've been cleaning, replacing parts, making simple adjustments etc. and then this failed. It was always going to be something I guess!
     
  8. Numone

    Numone Member

    Messages:
    90
    Quick update. The deck goes to the tech this Friday. He says he hasn't come across this problem before, but he's confident he'll fix it; I'll show him audiojones posts for assistance.
     
  9. kermit z

    kermit z Loud Music saves Lives!! Subscriber

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    Location:
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    That's awesome and great help from AudioJones. This is what makes AK so great :)

    Numone, keep us in the loop on the progress, would be nice to hear what happened in the end.
     
  10. Numone

    Numone Member

    Messages:
    90
    Well, AudioJones was 100% correct. The Pause/Play/Fast switch had indeed failed. Steve Bennett at Vintagetech in Surrey removed and dismantled the switch, and there he found additional unused points, so he relocated the respective connections to these and voila - it's all up-and-working again. Is said it took him around 1.5 hours, so it was both a fast and inexpensive fix. I'm over the moon and can't recommend Steve enough; he is excellent - and to AudioJones here for his insight and guidance. Incidentally, Steve said he's had a 3340 owner contact him yesterday with what sounds like exactly the same problem. He said he'd never seen before it in 25 years of working on TEAC R2R then two come along within 2 weeks!
     
    Last edited: Oct 9, 2018
  11. audiojones

    audiojones Jonesin' for audio Subscriber

    Messages:
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    Location:
    Central NJ
    Jeeze, if he did all that in only an hour and a half he’s really good! Glad you got it up and running again :music:
    That’s a great idea using an empty set of contacts with the same function, I’ll have to store that one away for the next time I run into one of these with the switch issue. Incidentally, this problem seems to be more common on the models that use 10.5” reels than it is on the 7” models. I’ve always figured that’s due to the increased amp draw it takes for the motor to start and run the heavy 10” reels since all of the current goes through the switch contacts. Keep track of that tech!
     

     

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  12. audiojones

    audiojones Jonesin' for audio Subscriber

    Messages:
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    Location:
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    BTW - I've got a 7" version of that machine on the bench right now. Nothing wrong with the switch though, just the usual stuck pinch roller linkage and a noisy reel motor.

    image.jpeg
     
  13. Numone

    Numone Member

    Messages:
    90
    Yeah, Steve has a great reputation which obviously I, together with his very full workroom, can confirm. Judging by the feedback I've seen on other vintage technicians here in the U.K. with the increased interest in R2R, there seems to be a "make hay" attitude toward their customers and charging huge sums for easy jobs, like belt replacement or freeing up the pinch roller assembly. But I guess if someone had picked-up a R2R for £5-600 then paying £200 for a "service" doesn't look too bad. However, from everything AJ said, the initial diagnosis of the problem on the bench, the location of the broken part, the amount of dismantling needed just to get to it, the repair itself and then the rebuild, this was no "easy" fix. Added to this of course, Steve had never seen the issue before and therefore, had never attempted it either. Given these facts, I'd braced myself for a big bill. Week he called me to say is was ready, and the cost I actually said "What - are you sure?"; Steve said "Well I can charge you more if you want!"
    All I can say is, he is thee "go to" guy for all R2R issues. He isn't just limited to R2R, but repairs all types of other vintage HiFi, such as cassette decks, amps and receivers. He had a colossal Marantz receiver there awaiting his attention, with a low left channel.
    For those who're interested, his website is https://www.vintagetech.co.uk/.
     
  14. Numone

    Numone Member

    Messages:
    90
    Dupe post... twit!!
     

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