8mm Forum: Sankyo 700 fault

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Posted by Gordon Parry (Member # 4650) on January 18, 2015, 05:19 AM:

Hi,
I recently brought this out of long retirement (12 years).
It had been boxed and placed in a dry attic. On starting,the
projector blew its main fuse. I changed the fuse and the 700
behaved normally on turning on... the light goes on at the
correct time on switching,and there is a gentle hum from the
speaker as normal. However, the motor does not start in fwd. or
reverse! If I connect the motor wires directly to a seperate dc
source,the motor runs well, I can even project a film with this
coarse set up. Any ideas????
Thanks.

Posted by Maurice Leakey (Member # 916) on January 18, 2015, 05:50 AM:

If it's a Sankyo your problem is almost certainly the micro-switches. There are quite a few of them for various functions, they are operated by the master control rotary knob.
Sankyos are great projectors, but their micro-switches are their main faults.

Posted by Gordon Parry (Member # 4650) on January 19, 2015, 12:29 PM:

Well possibly. I just had a very good look over the board and found
a track ,from the terminals of the motor supply cables to a bridge rectifier,slightly burnt and separated.So, I will replace the rectifier and do a track repair and see what happens:)

Posted by Gordon Parry (Member # 4650) on January 24, 2015, 07:50 AM:

Just an update...After a complete strip down,the 1000 uf 50v capacitors were replaced,and one 25 v 1000uf. One was shorted.
The bridge rectifier was also replaced and the board track repaired. After careful reassembly and thorough cleaning and
servicing, it projected close encounters of the third kind. There was a rock solid stable picture,with great sound! I now have again an immaculate Sound 700 in its as new original box [Smile]

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