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Author Topic: wild servo on technics 1500  (Read 3193 times)

Offline U47

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wild servo on technics 1500
« on: March 26, 2007, 05:37:52 PM »
Went to use my Technics 1500 yesterday and it refused to lock on speed. It apprears to be 'whining', as if the servo has gone berserk. I never noticed any strange noises like this before. I've owned about 7 of these decks over the last 15 years and this is the first instance of a servo issue I've experienced. Any ideas about where to start on this?

Rich Brown
Acoustic Arts
Portland, Oregon
Technics 1500 with King/Cello playback electronics, Stellavox SP-7, Technics 1500/Ampex MR70, Tascam BR-20 .

Offline docb

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Re: wild servo on technics 1500
« Reply #1 on: March 27, 2007, 06:10:22 PM »
A few things to check would be if the pinch roller pressure is sufficient, if the supply reel brakes might be dragging in playback mode, and you might also check the capstan motor control circuit - which requires a scope.
Dan "Doc B." Schmalle
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Offline slbender

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Re: wild servo on technics 1500
« Reply #2 on: September 13, 2007, 07:26:53 AM »

Hi Rich,

A friend of mine had the same thing happen recently with his Technics 1100a direct drive turntable... He hasn't fixed it yet, but bought a similar armless 1100a TT and just switched the arm from the old one to the recently acquired one.  That was his solution.

Anyway, its been about 5 months since you posted, so I was wondering if you solved it ?

BTW - I've been supplying a DIY Servo Fix Kit for most AKAI RTR machines that use direct-drive servo-controlled capstan motors, since the late 1990's.   Turns out these RTR's often exhibit similar symptoms when they age after 25 to 30 years.


-Steven L. Bender



Went to use my Technics 1500 yesterday and it refused to lock on speed. It apprears to be 'whining', as if the servo has gone berserk. I never noticed any strange noises like this before. I've owned about 7 of these decks over the last 15 years and this is the first instance of a servo issue I've experienced. Any ideas about where to start on this?

Rich Brown
Acoustic Arts
Portland, Oregon