Beaulieu 708 playback issues of sound

[Mark Barton]

Hello, when I play a sound film and rotate the knob to sound, the picture looses loop and the sound warbles. Please see the video on Youtube:https://youtu.be/wEH7V_GMmp0 Please advise, help always appreciated.

[Michael Beyer]

Hi Mark,
the Video is marked as private, so I cannot see it.
I don't know the english term for what we called in Germany "Schwungmasse" - the big wheel to stabilize the transport through the sound section. But is that wheel running in your machine?

[Brian Fretwell]

We normally say flywheel for that.

[Mark Barton]

Now public. thank you /Danke

[Rob Young]

Mark, I've been using a Beaulieu for over 20 years and as the previous two posts suggest, I think the most likely cause is that the capstan isn't turning.

Apologies if I'm suggesting things you already know or have tried - first check that the capstan spindle is turning. It should start turning as soon as the projector is powered up as it's belt driven by a separate motor. It can be had to tell, but pressing your finger lightly on the edge of it should confirm. Or try putting the projector into forward sound mode without a film and see if the rubber capstan pressure roller turns when engaged against it.

If it isn't working, it's most likely one of two causes. Remove the rear cover (3 straight edge screws and a top clip, but be careful when pulling the cover away form the main body as the internal speaker is hard wired, although there should be enough cable to allow you to move the cover out of the way).

The capstan motor is near the front, under the large capstan drive. It's belt driven and the usual cause is a snapped belt (I've had two go so far). They're available from Van Eck and easy to replace. They simply fit over the drive motor spindle and then around a grove in the main capstan.

A worse case is that the motor has failed (the motor spindle isn't turning when the projector is powered up - obviously be careful the cover removed and power supplied!)

Van Eck do have new motors, but something to consider is that this was a common problem with early 708's. For some reason, the manufacturers of the motor control board didn't quite follow Beaulieu specifications and some components on the original board are the incorrect value, leading to eventual failing of the motor.

I had this problem about 18 years back and the repair was handled by a competent repair guy as it was out of my league. At that time, new motor control boards were still available - not sure about that now.

His opinion was that replacing the motor would work, but that it may fail again at some point due to the mistakes on the control board.

Hopefully, if the capstan is the problem, then you only have a broken belt.

Good luck as these Beaulieu machines are superb when working well.

[John Paul Urizar]

Greetings

I have the same issue with my beaulieu projector. Did you pinpoint the issues based on the comments above ? Cheers John Paul

[Oliver Feld]

Mark
I might be wrong and maybe I got the problem wrong, but did You try to re-loop while the sound screening?
I think You shouldn’t re-loop as shown on picture 1 but do it left from the soundhead system as shown on picture 2.
This always helped me to stop the Sound warble...

[Rob Young]

Looking closely again at Mark's video and it seems that the capstan is working.

Maybe this thread from the old forum could help?

8mm Forum: Beaulieu 708 EL HTI - issue, help! (film-tech.com)

[John Paul Urizar]

Thank you Rob. I think that will help . Cheers John Paul