Eumig 938

[Stuart Bromley]

Hi everyone.
I have a Eumig 938 that hasnt been used for over 20 years, after a clean & dust down I switched it on, the bulb lit, works fine forwards but it wont rewind, does anyone have any ideas, is there a clutch or somwhere I should be loooking, there is no sound either an any channel but it all lights up.

[Paul Adsett]

Sounds like the usual Eumig problem of the rubber drive disc slipping. Remove the front cover and clean both rubber discs with isopropyl alcohol. Soak a q-tip with alcohol and wipe the discs with a scrubbing motion, repeat as necessary with clean q-tips until no more black debris comes off the discs. Also clean the metal drive disc with alcohol. Leave dry for an hour and everything should work fine.
The sound problem is much more complex. It's possible that the sound head is entirely worn out. Do you get hum from the speakers when you turn the volume control up? Are you running sound films which have a brown or grey magnetic stripe on the edges of the film? Do you have the instruction manual for the 938?

[Erik Snel]

As Paul said, clean the rubber discs. what worked for me is this: White Spirit on a cloth and spin the discs by hand. do this a few times and try again.

As for the sound. the 900 serie projector all have the same issue. the switch behind the red button get dirty and makes no contact. Quick fix: push the switch several time quickly and let it come back with no film in the projector. this may scratch the contacts clean enough the get the sound going. if not then the amp has to be disassembled and the switch cleaned by hand. i have made and instruction document on how to do this on an RS3000. yours has the same type of amplifier in it. 9 out of ten times the problem is fixed. I am playing with eumig machines for 20 years now and never had one with worn out sound heads.

[Stuart Bromley]

Thank you Paul /Erik I will do as you said & let you know how I get on. The projector is like brand new its only had about a dozen films through. The sound suddeny stopped working on both channels but the fuse is ok. I have a Bolex Sound 715, just ordered a set of new bulbs (the original works but after what around 30 years not sure for how long), I just dont like the clatter these machines with both spools at the back make! I am also trying to bring an old Fuji M3 back to life, just waiting for a new motor belt to arrive but it powers up ok. The things we do when we cant get out! Thanks for your help so far

[Stuart Bromley]

Paul you mentioned you had made and instruction document on how to do this on an RS3000 & has has the same type of amp has this been posted anywher so I can see what may need doing Thanks

[Erik Snel]

it was me and not paul who mentioned this. i think i will make a post soon about this.

[Maurizio Di Cintio]

I don't think the problem with the sound is caused by a dirty record switch button: models 926, 938 have different buttons from the majority of series 900's. IMHO it might be a capacitor that failed; to make sure it is the problem, if you have another sound and perfectly working projector, you can try recording on your 938 and playback the film on the other machine: if there is sound, then it's a playback amp issue: on this machine (as well on 926 and 940) the record and playback amplifiers are totally separated so it might work in record mode but not in playback and there is no way to know until you use a different projector.
Eumig's sound heads are indeed less durable than other makes: it is sad to say but it's a fact; I am not just referring to wear excised by the soundtrack: the problem is almost all sound heads for the 900 Series (except lesser models), have something I'd call a bug: the balance track Rec/PB head comprises just two tiny, flimsy mag alloy blades/layers: if poorly attached to each other, eventually they will split even if not totally worn. When that happens, playback is relatively unaffected, as long as the gap between the layers is still very small; but recording suffers from poor magnetization: in fact for good quality recordings, the smaller the gap, the better. The larger than normal gap will cause below average performances that sum up along the chain (REC + PB) and in this case the problem will become more apparent. Same story with the progressing of the problem until eventually the gap between the layers is so wide (in relative terms, of course) that the head will not simply pick up or record any signal from/to the soundtrack any more and all you'll get is sheer background noise (hum and hiss).

The main track head is relatively less prone to such problems because it's made of 4 blades/layers and is far more resilient. And because the majority of film we watch i are "track 1 only, that's why this issue mostly goes unnoticed. Still it's there or will become apparent at some point. A bad splice may start the problem. That's why I suggest to have a spare pressers' cartridge with the balance stripe's pressers disabled. It's the only way to let the track 2 head last as long as the main track's. The two cartridges can be swapped in seconds any time you need toswitch from 2 track to 1 track playback or record. I've never regretted this care.

[Paul Adsett]

That suggestion from Maurizio is really worthwhile following. I took this advice several years ago when Maurizio first posted it, and removed the balance stripe presser from a spare presser cartridge, and it is installed as the default cartridge in my 938, except of course when I wish to replay/record a stereo film. So far my balance track sound remains as loud and clear as the main track.