8mm Forum: elmo st-800 problem

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Posted by Terryll Loffler (Member # 888) on October 06, 2007, 09:59 AM:

my projector recently became problematic. the issue is that the 18/24 switch does not work and it seems to be stuck on a frame rate faster than 24. i have watched films that i shot at 24fps and they still run fast. so to overview the projector is running too fast and cannot be switched. is this an electrical problem, belts? anyone have this issue before? i hope this is an easy fix because the projector is in amazing shape and i would hate to toss it. thanks.

Posted by Mike Peckham (Member # 16) on October 07, 2007, 09:26 AM:

Hello Terryll

Welcome to the forum [Smile]

Don't know if this will help at all but I once had exactly the same symptoms you describe on an ST600. I know exactly what the problem was in that case because I caused it!

On the ST 600 at least there is a small board on which are mounted two adjustable pots, these regulate the speed, one for 24fps and the other for 18fps. I tried adjusting these and managed to break one of them, the result was that the speed set itself at a constant rate a little faster than 24fps and remained there regardless of where the speed control switch was set.

It might be that there is a problem on that board on your machine, perhaps the pots have become oxidised and are not making a circuit as they should, or maybe there is another component on there that has "gone down".

In my case I was able to remove the board and send it complete to Kevin Faulkener and he replaced the adjustable pots and sent it back to me with instructions of how to set it up again.

Don't know if that's any help but it might help to narrow down where to look for the cause of the problem at least.

Mike

Posted by Terryll Loffler (Member # 888) on October 08, 2007, 10:42 AM:

ok. i found the pots, they were stuck with oxides but i managed to turn them. the speed adjusted, but it seems that it may still be running faster compared to my chinon SP-330MV. but i would like to remove the oxides but what do you think is best? alcohol? wd-40?

UPDATE: so i did a complete cleaning of the pots and then adjusted the speed the best i could and it is still running way too fast. the pots don't seem to adjust much though, just fast or faster. there is not gradual speed change. so unless there is some other problem fix that any of you could help me with, this projector is pretty much useless. bummer.

[ October 08, 2007, 01:03 PM: Message edited by: Terryll Loffler ]

Posted by Kevin Faulkner (Member # 6) on October 10, 2007, 04:29 AM:

Sounds to me like there may be a problem in the speed control circuitry. I dont have a circuit for the machine but from what I remember its not that different to ST600.

One thing to make sure is that the speed switch is working properly. Use some switch cleaner. If this is NOT changing the speed then I would definitely say that a component has dies in the control circuit. This should be very easy to sort out by someone with some electronic knowledge without the need to scrap the machine.

Kev.

Posted by Terryll Loffler (Member # 888) on October 14, 2007, 04:24 PM:

i think the switch is fine. it changes speeds with the two different frame rates, but the speeds for both are too fast. so as you would guess it must be something with the circuitry. bummer.

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