Film-Tech Forum ARCHIVE: Kodak Pageant

This is topic Kodak Pageant - audio noise/distortion in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Michael Robinson (Member # 10329) on 02-18-2019, 03:50 PM:

The potentiometer for the volume control creates terrible distortion thru the speaker when ever it is adjusted. Volume doesn't seem to increase or decrease, just loud distortion.

Any thoughts on how to fix this?

Thanks,
Michael

Posted by Tyler Purcell (Member # 9213) on 02-18-2019, 09:22 PM:

Have you tried cleaning the potentiometer? Sounds like a bad pot that's grounding out.

Posted by Tony Bandiera Jr (Member # 2365) on 02-18-2019, 10:35 PM:

Also check the tubes if it has any, make sure they are fully seated in the sockets (might be a good idea to pull and re-insert them a few times to break up and corrosion in the contacts or tube pins.)

If it is solid state and not tubes, or of the tube trick doesn't work, start looking for bad electrolytic caps, they will cause problems if they have dried out.

Posted by Michael Robinson (Member # 10329) on 02-21-2019, 09:06 AM:

Thanks for the suggestions. I will take a look.

Posted by Jim Cassedy (Member # 4115) on 02-21-2019, 04:05 PM:

Back in the 1970's I worked part time in the AV Department of a large college
on Long Island maintaining their large collection of Pagent Projectors & which
were my least favorite machines to work on.

The two most common causes of lousy/distorted sound that I recall were:
1) Noisy volume control. They really used cheap pots in those projectors!
We often replaced them with ones from Radio Shack, which
were probably equally inexpensive, but much better made.
2) The output transistors seemed to slowly, rather than suddenly,fail.
We often suspected thermal aging/failure due at least partly to the fact
that we almost always found the heat sink compound Kodak used had
almost always dried up in to an almost epoxy-like mass that blocked
heat better than transferring it. ( I think this was corrected in later models)

The transistors were common types that I think we used to order through
Lafayette Electronics, since we weren't too impressed with Kodak's choice
of electronic components in general.
The circuit boards in some of those Pagents definitely didn't seem of a
quality one would expect from Kodak. Some of them looked like they'd
been designed & etched in someone's basement as part of a science project.

Posted by Mark Gulbrandsen (Member # 72) on 03-01-2019, 06:42 PM:

quote: Jim Cassedy
Back in the 1970's I worked part time in the AV Department of a large college
on Long Island maintaining their large collection of Pagent Projectors & which were my least favorite machines to work on.

I was also in a similar position except for a large school district in the Chicago burbs. We had well over 800 16mm projectors and about half were Pagents. Most of the rest were Eiki and a few B&H which we did not bother to fix and instead replaced with Elmos. The Kodaks were very easy to work on once out of the case. No more difficult than the Eikis and the Kodaks were uber easy on the Districts film library content. Yes, the amps were cheesy but they worked ok. I actually do not rmember ever repairing an amplifier in a Pagent.

Mark

Posted by Frank Angel (Member # 248) on 03-12-2019, 02:00 AM:

Just dug 2 Pageants out of the "Fix These" bin. Both had the same scratchy, dirty audio that you describe. All I did after maneuvering the amp out of the case and before going thru the hassle of fully replacing the pot, I just force-sprayed the fabulous Caig DeoxIT Gold contact cleaner & lub into the pot's connection openings...let it sit there for 10 min minutes then worked the contact wiper turning it back and forth a bit and the static & scratchy noise just disappeared. Give it a try before going thru lots of agita pulling and replacing that pot. But no doubt, it is that pot that causes the noise.

Posted by Helmut Maripuu (Member # 2281) on 03-12-2019, 04:49 PM:

https://www.youtube.com/watch?v=oDF9jqRy3U0