8mm Forum: Eumig S807D Lamp not working

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Posted by Ingo Helbig (Member # 5567) on September 18, 2016, 02:15 AM:

Can anyone tell me why the lamp on my Eumig S 807 D projector has stopped working? Until recently the projector worked perfectly. The other day I was projecting a film in forward and then went into reverse with the lamp on. After reversing in this way for a time, I turned the lamp off and continued playing in reverse. When I next switched to forward motion, the lamp no longer worked. I have tried replacing the lamp and the new one also doesn’t work. Currently the lamp glows at a very low level in all positions of the control knob (even stop). I am unsure if this was happening before the lamp stopped working at full intensity.
I’d really appreciate someone’s help with this. Have I knocked a switch or some part of the projector that I’m unaware of? Is there a hidden fuse somewhere?

Thanks Ingo Helbig

Posted by Maurice Leakey (Member # 916) on September 18, 2016, 04:18 AM:

It is probable that the main control knob physically operates certain micro switches. Unfortunately, over time the spring in such switches fail, thus not switching on/off.

Posted by Brian Fretwell (Member # 4302) on September 18, 2016, 05:29 AM:

All the sound Eumigs with the 12v 100w halogen reflectors I own of have lamp pre-heat as soon as switched on so it does look like what Maurice said. Though with this make I would think it would be an open contact switch not a micro switch. The S903 I have just taken the back off is like that so it should be easy to check & clean the contact area and check no wire connectors have come adrift as it is operated by a cam at the back of the main rotary control.

Posted by Paul Mason (Member # 4015) on September 18, 2016, 06:27 AM:

The lamp plug is the obvious suspect as it carries a heavy current. Over time the lamp contacts heat up slightly, corrode and the increase in resistance causes more heating until the contact is too poor to carry the current. They are difficult to clean and the best answer is to replace the plug with a new one as these are still available.

Posted by Paul Mason (Member # 4015) on September 18, 2016, 06:28 AM:

Posted by Andrew Woodcock (Member # 3260) on September 18, 2016, 06:40 AM:

If it were the lamp connector at fault here Paul, almost certainly the lamp would not pre heat as it is doing.

Almost certainly it will be poor contact from a cam lobe to an additional lamp switch which carries the full lamp voltage supply to the lamp holder, micro switch or otherwise.

The advice already given by Maurice and Brian appears the most feasible from the description of the actual fault.

Posted by Paul Mason (Member # 4015) on September 18, 2016, 10:11 AM:

I take your point Andrew and I agree that Brian and Maurice's remedies should be tried first.

Posted by Steve Klare (Member # 12) on September 18, 2016, 11:47 AM:

Agreed:

It sounds like a switch has had its day and gone wherever dead switches go! A lot of projectors have an on/off lamp switch, I'm thinking this one has more like a low/high switch instead.

I'm going to have to break my Eumig 800 series some day: I've had it 14 years now and other than the cruddy grounding I've had so little trouble with it I'm not really sure what goes on inside there! [Wink]

Posted by Maurice Leakey (Member # 916) on September 18, 2016, 02:07 PM:

The S807D does not have a mains switch.
As soon as power is connected the motor runs and the lamp comes on at pre-heat.
The operation of the control knob then tilts the motor to contact one of the plates which, in turn, rotate, thus moving the mechanism.

Posted by Terry Sills (Member # 3309) on September 18, 2016, 02:23 PM:

Always try the most simple solutions first. I agree with Paul. It could be corrosion either on the pins of the lamp or within the lampholder. I have had this problem numerous times. Sometimes when you replace the lamp with an old stock lamp this happens because the pins corrode over time. Examine the pins of the lamp and if they are not bright and shiny just scrape the pins with a craft knife or similar to remove the corrosion. If this does not work then the corrosion is most likely within the lampholder and a few withdrawals and insertions together with some wiggling of the lamp will often work. If not then a replacement of the lampholder is the next most ecomonical step before you go on to more serios issues.

Posted by Paul Adsett (Member # 25) on September 18, 2016, 03:06 PM:

10 TO 1 it's the lamp socket,

Posted by Andrew Woodcock (Member # 3260) on September 18, 2016, 06:11 PM:

Not unless the pre heat lamp light is erratic / intermittent also Paul.

This is unclear so far, but if by touching the lamp holder after cleaning the lamp pins, the low light stays on constantly and it still has the full lamp power fault, then it must be a fault on the master switch mechanism somewhere. Could be mechanical, could be electrical equally, of course here.

Posted by Ingo Helbig (Member # 5567) on September 19, 2016, 02:40 AM:

Thank you gentlemen for all your thoughts. What an amazing forum this is with everyone pitching in to help. Cleaning the lamp connector came to nothing, so I began searching for a switch. Nothing was accessible from the rear, but I soon worked our the front panel is easily removed and behind that is a microswitch within the control knob space. It turns out the plastic lever which operates the switch when the knob is turned to the lamp position is broken. I have made temporary repairs by closing the switch with a piece of cardboard. The lamp of course now comes on fully as soon as the power is connected, which is not ideal, but at least I can project film again. I've attached an image of the switch area. I may now try dissembling the knob mechanism to see if the plastic lever can be replaced/repaired. Has anyone done this before? Would I just be opening a can of worms if I tried it?

Posted by Andrew Woodcock (Member # 3260) on September 19, 2016, 03:14 AM:

Better to just try to source a similar sized micro switch Ingo of correct electrical rating or larger,also correct physical size and fit where the mounting screw holes are concerned.

Micro switches are very easily found and very readily available. I doubt it could be too difficult to source another suitable one from your local electronics store there in Oz.

I'm sure someone here will have some kind of service manual for this series of projector giving you an exploded engineering drawing of the assembly so you can work out how to dismantle the assembly correctly and safely without damage to any component.

Good luck Ingo.

Posted by Brian Fretwell (Member # 4302) on September 19, 2016, 06:40 AM:

I don't think the micro switch is faulty, just the lever from the cam, that operates it. That said, changing both at this time might be a good idea, he doesn't want to take it apart twice, if it fails soon after.

Posted by Andrew Woodcock (Member # 3260) on September 19, 2016, 01:09 PM:

Youre right Brian sorry.
I thought it was the micro switch lever which had broken but for those who know these projectors well like Brian here, it was of course, an interlinked lever between cam lobe and switch apparently.

Apologies to Ingo for the incorrect advice given there.

Posted by Ingo Helbig (Member # 5567) on September 20, 2016, 08:36 PM:

Thanks Andrew and Brian, Yes its the plastic lever from the cam which seems to be either broken or come adrift. its located behind the knob mechanism shown in the picture. I'll have a go at dissembling it sometime soon and see if its repairable. Thanks again for everyone's help. Ingo

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