8mm Forum: Eiki st/m no sound

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Posted by Jason Moffatt (Member # 4416) on August 11, 2018, 09:37 AM:

Hi all, Just picked up an eiki st/m and it plays film fine but there is no sound.Exciter lamp works and it seems to be focused in the correct place on the soundtrack as i have another identical machine with good sound to compare it with, also the amp fuse is ok.When the amp is turned on the speaker crackles and pops a bit but there is no hum like with the other one.Any ideas?

Posted by Maurice Leakey (Member # 916) on August 11, 2018, 11:33 AM:

It's an old model, and also may have been badly stored.
Probably a capacitor/s need replacing.
I had the same problem with an M1 which had no sound, and my engineer replaced a 100 uF capacitor.

Posted by Jason Moffatt (Member # 4416) on August 12, 2018, 11:58 AM:

Thanks for the reply maurice,so i will need to remove the amp to see the capacitors?, and would it only be one that has failed or will a few need replacing?.

Posted by Maurice Leakey (Member # 916) on August 12, 2018, 02:48 PM:

Jason
If you are not familiar with amplifiers it seems that you need professional help to diagnose your sound problem.

Posted by Can Sanalan (Member # 5988) on August 13, 2018, 02:10 AM:

What you can do Jason is take out the amp unit by removing a couple of screws and disconnecting two wires which if I remember correctly are located on the right side (when facing the projector from the side the cover is off) and spraying some contact cleaner, I used Servisol, into the pots of the volume control knob. Do it for the bass and treble control pots too. Spray into the tiny holes they have and twist the knobs back and forth to work it in.
That’s what I did for my ST/M and it solved my sound issue.
If that doesn’t work for you then like Maurice said you’ll have to replace the capacitors on the board which by the sounds of it could be the real issue but give the contact cleaner a go first.
Good luck.

Posted by Jason Moffatt (Member # 4416) on August 14, 2018, 06:56 AM:

Maurice & can, thanks for the replys.Well that was easy, just took out the amp and sprayed the pots with switch cleaner and poked around a bit inside and it now works perfect with no crackle from the speaker now either just a nice hum.So not shure what it was exactly, maybe a dry joint ?.

Posted by Maurice Leakey (Member # 916) on August 14, 2018, 07:28 AM:

Pleased to hear it, Jason. Good show.

Posted by Can Sanalan (Member # 5988) on August 14, 2018, 12:24 PM:

Yay! Glad to hear it’s working:)
Enjoy.

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