Tascam TSR-8 Tension issue

Discussion in 'TASCAM Analog Forum' started by stevealex, May 23, 2020.

  1. stevealex

    stevealex New Member

    Joined:
    May 2020
    Messages:
    9
    Likes:
    1
    Gear:
    TSR-8
    Hey all,
    My first post here. I have a TSR8 that I am all of a sudden having playback speed issues with. I read the manual and found the adjustment pots for the two reels. I don't have a tentalometer, but I got them to feel pretty balanced. The playback is normal for a few seconds, then all of a sudden it starts speeding up, or maybe even slowing down. Is this because I don't have the tension set right? or is there some control board part that might be faulty? Thanks for any advice you can offer
  2. SkywaveTDR

    SkywaveTDR Active Member

    Joined:
    Feb 2014
    Messages:
    552
    Likes:
    89
    From:
    Chicago area
    Gear:
    Teac, Tascam, Sony
    I had to go look but the TSR8 is a belt drive deck and like all other decks has a capstan bearing that requires yearly oiling and is also known on occasion to need a new Pinch Roller rebuild as they get sticky and will affect the speed as well. So which one is wrong? I can only say if it is in my shop. Adjustments of tension by a person that has no measuring device is a sure fire way to have the tensions off. I see local shops do X1000 and X2000 servo tension decks all the time and do they get them even close? NO not at all. I keep on turning then down from 190 to 200 g/cm when they are suppose to be at 50g/cm.
    If you are going to work on the product then get the right tools, with MRL alignment tape and Tentelometer you can easily be into $550 just for those two if not more. You can never work on the deck correctly with out these tools and tapes. That is just the way it is. Then on top of that guessing that the tension is the problem complicates the analysis and is not at all a good guess.
  3. stevealex

    stevealex New Member

    Joined:
    May 2020
    Messages:
    9
    Likes:
    1
    Gear:
    TSR-8
    Thanks @SkywaveTDR ! I think the parts you mentioned, like the rollers, are good. It was fully serviced by well-known tech in NC before i bought it from a very respected owner! Then I only used it for several hours since over the past few years and it ran perfectly until recently. Could it have been changing speed because I was at the end of the tape roll? I definitely messed up the tension now by guessing and tweaking blindly.The equip needed to properly diagnose is gonna be cost prohibitive, so either I hack away at it or send it to a pro. What would it cost to have a pro tweak it? thanks, steve
  4. wkrbee

    wkrbee Active Member

    Joined:
    Sep 2012
    Messages:
    219
    Likes:
    42
    Verify the capstan belt is not slipping.
  5. SkywaveTDR

    SkywaveTDR Active Member

    Joined:
    Feb 2014
    Messages:
    552
    Likes:
    89
    From:
    Chicago area
    Gear:
    Teac, Tascam, Sony
    Cost can not be stated based on a symptom that we do not know what is the cause.
    Right now I have so many unit here that I can not take more in maybe for at least a few months.
  6. stevealex

    stevealex New Member

    Joined:
    May 2020
    Messages:
    9
    Likes:
    1
    Gear:
    TSR-8
    @wkrbee Can you point me in the right direction toward checking the capstan belt? I looked through the manual, cant find it anywhere. The playback is fine for a few minutes, and then it speeds up sometimes significantly, sometimes slightly. If I stop playback and restart, then it plays at normal speed again
  7. SkywaveTDR

    SkywaveTDR Active Member

    Joined:
    Feb 2014
    Messages:
    552
    Likes:
    89
    From:
    Chicago area
    Gear:
    Teac, Tascam, Sony
    On the manual page 6 is shows the unit with top front panel removed and the motor pulley and belt are clearly visible plus it notes the capstan shaft which is all cases links to the flywheel that usually has the belt around it to the motor pulley.
    Also in many decks there is a switch and a Pitch control that is a pot that can get dirty. Otari MX5050 is very well known for this. The TSR8 also makes use of U5 4066 IC which is a Cmos bilateral gate and these are parts that in other equipment are known to fail. These are the switches of the three modes of operation of the capstan servo and these are all possibles but start with oiling the top motor bearing, Capstan bearing by taking the capstan shaft out and I use AMS Signature series motor oil that is a synthetic and has given me wow and flutter as low as .0135% in a BR20. The head base needs to be removed to get to the flywheel and belt- doing it the other way is more amateur and does not oil the deck correctly.
    Last edited: Jul 16, 2020
  8. stevealex

    stevealex New Member

    Joined:
    May 2020
    Messages:
    9
    Likes:
    1
    Gear:
    TSR-8
    @SkywaveTDR @wkrbee I bought a new capstan belt, got the TSR8 on the bench, gonna replace it tomorrow. fingers crossed. Thanks for the advice!!
  9. SkywaveTDR

    SkywaveTDR Active Member

    Joined:
    Feb 2014
    Messages:
    552
    Likes:
    89
    From:
    Chicago area
    Gear:
    Teac, Tascam, Sony
    Remember to oil the capstan bearing- too many people skip this and then never get good results.
    Why put new spark plugs in a car if you are not going to put gas in it?
  10. stevealex

    stevealex New Member

    Joined:
    May 2020
    Messages:
    9
    Likes:
    1
    Gear:
    TSR-8
    Is that underneath the capstan motor?? I got the belt swapped out, and seems to have solved the problem!! thanks again!
  11. SkywaveTDR

    SkywaveTDR Active Member

    Joined:
    Feb 2014
    Messages:
    552
    Likes:
    89
    From:
    Chicago area
    Gear:
    Teac, Tascam, Sony
    The capstan bearing is the thing the capstan shaft goes into and takes all the load of the pressure from pinch roller. This is in front of the flywheel.