Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Tom Felker
 
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Default Sync motor failures on Allied TR-1035 reel-to-reel tape recorder

Hi,

I recently dusted off an old Allied Solid State TR-1035 reel-to-reel tape
recorder (circa 1969) in an attempt to transfer some old tapes to the
computer. After fixing mechanical problems, it worked fine, until, after
about an hour of playing, the motor died.

The motor was quite hot. Even after cooling, it would no longer start on
its own when the unit was powered up. You could start it spinning by hand,
but it spun very slowly and didn't have enough torque, so it would stop as
soon as you engaged the drive mechanism. If you started it the wrong way,
it went faster, but still probably not as fast as it once went.

We bought another similar-looking Allied tape recorder from eBay, and
after facing insurmountable drive-mechanism problems, we took its motor,
identical to the failed one, and installed it in the first recorder. Lo
and behold, it worked great... until after about 5 minutes of playing, the
second motor failed, in exactly the same way as the first one had.

The puzzling thing is, the second motor was not at all hot when it failed.
Moreover, it had been run in the second recorder for much longer than 5
minutes at a time without incident.

I believe this is a synchronous motor. It only spins at one speed, tape
speed is adjusted mechanically. It's labelled "M536D / 120V." It has
three wires, red, green, and yellow. Red and green are hooked up to a big
1.5uF capacitor. Red is also connected to the primary coil of the
transformer, the other lead of which is connected to the power cord.
Yellow is connected to the same power terminal via, in parallel, a
tape-detector switch and a component labelled "0.1(K) 400 JB." I can
describe more of the wiring if necessary.

My questions a Is there any way either of these motors can be
salvaged? Is there a way the first recorder could be causing motors to
fail? Could it be fixed? And failing that, does anyone know a good
audio-tape to CD service?

Thanks for your help,
--
Tom Felker,
http://vlevel.sourceforge.net - Stop fiddling with the volume knob.

In order to understand recursion you must first understand recursion.

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Tom Felker wrote:
I recently dusted off an old Allied Solid State TR-1035 reel-to-reel
tape recorder (circa 1969) in an attempt to transfer some old tapes
to the computer. After fixing mechanical problems, it worked fine,
until, after about an hour of playing, the motor died. [...]
Red and green are hooked up to a big 1.5uF capacitor.


It could be that this capacitor is dying of old age. You might try
replacing it with a 1.5 uF, 125 V AC (or better) capacitor. You can't
get this at Radio Shack. Strangely enough, you may be able to get it at
the hardware store - some ceiling fans use similar capacitors for their
motors. Try to get 1.5 uF if you can - either on its own or as part of
a multi-capacitor assembly. If you can't get 1.5 uF, it might be worth
buying a 2 uF capacitor for experimental purposes. Disconnect the
existing 1.5 uF cap and wire the new one in its place. If you have a
multi-capacitor assembly, insulate the unused wires individually with
electrical tape. Try the motor again. If you got a 1.5 uF capacitor
and the motor operates OK, you're probably good to go. If you got some
other capacitor and the motor mostly works - it runs cool but possibly
at the wrong speed or with reduced torque, then it's probably worth
seeking out a 1.5 uF capacitor and trying again.

Something else you might check - can this deck be set to operate on
multiple line voltages? 100, 120, 220, 240 are common choices. If so,
make sure it's set for the right line voltage.

Yellow is connected to the same power terminal via, in parallel, a
tape-detector switch and a component labelled "0.1(K) 400 JB."


This is probably an 0.1 uF, 400 V capacitor, that helps reduce arcs at
the contacts of the tape-detector switch when it opens.

Matt Roberds

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Michael A. Terrell
 
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Tom Felker wrote:

Hi,

I recently dusted off an old Allied Solid State TR-1035 reel-to-reel tape
recorder (circa 1969) in an attempt to transfer some old tapes to the
computer. After fixing mechanical problems, it worked fine, until, after
about an hour of playing, the motor died.

The motor was quite hot. Even after cooling, it would no longer start on
its own when the unit was powered up. You could start it spinning by hand,
but it spun very slowly and didn't have enough torque, so it would stop as
soon as you engaged the drive mechanism. If you started it the wrong way,
it went faster, but still probably not as fast as it once went.

We bought another similar-looking Allied tape recorder from eBay, and
after facing insurmountable drive-mechanism problems, we took its motor,
identical to the failed one, and installed it in the first recorder. Lo
and behold, it worked great... until after about 5 minutes of playing, the
second motor failed, in exactly the same way as the first one had.

The puzzling thing is, the second motor was not at all hot when it failed.
Moreover, it had been run in the second recorder for much longer than 5
minutes at a time without incident.

I believe this is a synchronous motor. It only spins at one speed, tape
speed is adjusted mechanically. It's labelled "M536D / 120V." It has
three wires, red, green, and yellow. Red and green are hooked up to a big
1.5uF capacitor. Red is also connected to the primary coil of the
transformer, the other lead of which is connected to the power cord.
Yellow is connected to the same power terminal via, in parallel, a
tape-detector switch and a component labelled "0.1(K) 400 JB." I can
describe more of the wiring if necessary.

My questions a Is there any way either of these motors can be
salvaged? Is there a way the first recorder could be causing motors to
fail? Could it be fixed? And failing that, does anyone know a good
audio-tape to CD service?

Thanks for your help,
--
Tom Felker



This is in Sams TR-53 I will dig my copy out in the morning to see if
there are any specs on the motor, and if I have any in my old spare
parts.

--
Link to my "Computers for disabled Veterans" project website deleted
after threats were telephoned to my church.

Michael A. Terrell
Central Florida
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Tom Felker
 
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On Sun, 14 Aug 2005 23:17:38 +0000, mroberds wrote:

Tom Felker wrote:
I recently dusted off an old Allied Solid State TR-1035 reel-to-reel
tape recorder (circa 1969) in an attempt to transfer some old tapes
to the computer. After fixing mechanical problems, it worked fine,
until, after about an hour of playing, the motor died. [...]
Red and green are hooked up to a big 1.5uF capacitor.


It could be that this capacitor is dying of old age. You might try
replacing it with a 1.5 uF, 125 V AC (or better) capacitor. You can't
get this at Radio Shack. Strangely enough, you may be able to get it at
the hardware store - some ceiling fans use similar capacitors for their
motors. Try to get 1.5 uF if you can - either on its own or as part of
a multi-capacitor assembly. If you can't get 1.5 uF, it might be worth
buying a 2 uF capacitor for experimental purposes. Disconnect the
existing 1.5 uF cap and wire the new one in its place. If you have a
multi-capacitor assembly, insulate the unused wires individually with
electrical tape. Try the motor again. If you got a 1.5 uF capacitor
and the motor operates OK, you're probably good to go. If you got some
other capacitor and the motor mostly works - it runs cool but possibly
at the wrong speed or with reduced torque, then it's probably worth
seeking out a 1.5 uF capacitor and trying again.

Something else you might check - can this deck be set to operate on
multiple line voltages? 100, 120, 220, 240 are common choices. If so,
make sure it's set for the right line voltage.

Yellow is connected to the same power terminal via, in parallel, a
tape-detector switch and a component labelled "0.1(K) 400 JB."


This is probably an 0.1 uF, 400 V capacitor, that helps reduce arcs at
the contacts of the tape-detector switch when it opens.

Matt Roberds


Thanks alot for the tips. I was able to simply take the capacitor from
the second recorder and install it in the first, and so far the motor has
been running fine. And now if this one fails I'll know where to find
another.

Michael, thanks for the offer, but it doesn't look like I'll need any
spare parts. I've learned that the motors themselves are fine, and I have
two of all the other parts, enough to make a working Frankenplayer.

Have fun,
--
Tom Felker,
http://vlevel.sourceforge.net - Stop fiddling with the volume knob.

Try not! Do! or do not. There is no try.
-- Yoda

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