8mm Forum: Eumig Mark S709

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Posted by Lee Bombard (Member # 3740) on June 30, 2013, 12:11 PM:

I'm trying to get a Eumig Mark S709 up and running and it's in terrific condition in all regards except the audio plays back sounding like a boat motor...
Before I have it serviced by a tech any thoughts on anything I might try first to troubleshoot?
Thanks!

Posted by Lee Bombard (Member # 3740) on June 30, 2013, 07:48 PM:

Looks like the 709 needs a replacement sound head.
Anyone have one for sale?

Posted by Mike McCord (Member # 3767) on July 01, 2013, 08:01 AM:

If the "motor-boating" sound (hum) is adjustable with the volume control, it is most probably in the direction of a bad sound head.
If the hum is not reduced by the volume control, then look in the direction of bad power supply filter capacitors. This is an old/common problem in the day of radios and TV's built with vacuum tubes.
PM me for more troubleshooting assistance...

Posted by Lee Mannering (Member # 728) on July 01, 2013, 08:20 AM:

Hi Lee. It could be that the sound pressure pad/pinch roller rocker is not free on its shaft. I had this as they tend to oxidise with age. Check that it is moving freely and smoothly when you turn the control knob for sound. Also well worth cleaning the black rubber pinch roller and silver capstan as you at it.

Check 1 is moving freely on its mounting shaft and 2 goes up and down.

Clean 3 with Isopropyl (audio head cleaner) on a cotton bud and also the metal capstain above it by rotating.

Underneath 2 the black swinging mount you will see some other metalwork which also needs to move freely.

Hope this helps.

Posted by Lee Bombard (Member # 3740) on July 01, 2013, 02:32 PM:

Lee - All the points you illustrating seem to be acting as they should. Can I assume that points to a bad sound head?

Mike - Sent you a PM.

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