8mm Forum: Beaulieu 708 EL HTI

This is topic Beaulieu 708 EL HTI - issue, help! in forum 8mm Forum at 8mm Forum.

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Posted by Flavio Stabile (Member # 357) on February 09, 2013, 03:33 AM:

Hi All,

my recent buying is this projector I was looking for since years!

Unfortunately I'm experiencing the following problem: when the main knob is rotated in the sound position, during the normal projection, the main loop of the film is completely lost because the film is trailed by the loop sensor roller support completely on the right (i.e. outside the projector).

The image of course becomes instable on the screen and no sound can be heard. Even the sprocket coming to the rear reel become a bit damaged!

Any help?

Flavio

Posted by Ricky Daniels (Member # 95) on February 09, 2013, 04:15 AM:

Hi Flavio,

It sounds like an issue with the optical sensor for the capstan roller, try giving the sensor a clean.

Good luck,
Rick

Posted by Flavio Stabile (Member # 357) on February 09, 2013, 04:40 AM:

Hi Ricky,

thanks for your reply... but, where is the sensor?

I'm preparing a video to show the defect...

Flavio

Posted by Flavio Stabile (Member # 357) on February 09, 2013, 07:52 AM:

And here is the video...

https://vimeo.com/59293411

Hope someone could help...

Not yet understood where is located the optical sensor for the capstan.

Posted by Lee Mannering (Member # 728) on February 09, 2013, 08:42 AM:

Flavio. The fault may show up better if you project some white leader film at 18fps. Just a thought.

I had a Eumig once that did this and all it turned out to be on close inspection was a loose screw on one of the two pull through sprocket wheels. A quick tighten up and fixed.

Posted by Flavio Stabile (Member # 357) on February 09, 2013, 10:24 AM:

Just wondering if it could be a claw problem...

I'm trying to project, in mute position, a film at 18 fps and the image on the screen is not really stable. The inter frames line, if the film is out of frame, on the screen is quite instable.

There is also a strange, not constant, noise coming from inside the objective, close to the film guide.

[Frown]

Posted by Hugh Thompson Scott (Member # 2922) on February 09, 2013, 11:10 AM:

The things that came to my mind Flavio would be the pressure
of the rubber wheel on capstan maybe there's not enough, or
the rubber might need replacing causing slippage or the rear
pressure plate in the gate might need some attention.

Posted by Lee Purkis (Member # 2523) on February 09, 2013, 11:38 AM:

I would try cleaning the brass strip inside the loop sensor, it looks like it is sticking. The lower sprocket part which moves back toward the roller should balance out somewhere in the middle when turned to sound position but it appears to jump either all the way forward or all the way back. So there is a good chance that the brass strip is very dirty and sticking. The sprocket should slide backward/forward very smoothly, you can test this just by moving it backward and forward with your hand. If it feels very rough/sticking you need to clean the brass strip for sure.

Posted by Flavio Stabile (Member # 357) on February 09, 2013, 12:53 PM:

Hi Lee,

I tried again without any film and even without power supply...
The entire block around the sprocket (sprocket support) can be moved very easily.
When the main knob is comnpletely rotated on "sound" position, the sprocket support goes completely in the right but with my fingers I can move again towards the capstan withour any resistance.
If I do this operation whekn the projector is running, but without any film, I can notice a change in the speed of the projector.
When it is completely far from the capstan the speed is higher than normal, when I move it towards the capstan the speed decreases again, I would say returning normal.

Hi Hugh,

how can I regulate or check the pressure of the film gate?

Flavio

Posted by Hugh Thompson Scott (Member # 2922) on February 09, 2013, 01:34 PM:

On that Flavio, I have no idea, as I have never seen the inside of
one.A friend of mine had one some years ago from Derann, but
he traded it in for something else.Are you sure that there is no
slip between the capstan & rubber roller?
I don't even know if the rear plate is accessable to check the
spring.Surely someone on this forum has one of these machines.

Posted by Flavio Stabile (Member # 357) on February 09, 2013, 02:43 PM:

No Hugh, no slip between the capstan and the roller...

It seems to me that the motor of the capstan is not working as expected. If I understood well, the concept behind the "motorized capstan" is that it should be controlled by the loop tightener.
However, in the sound position, the film is completely trailed by the capstan, leaving to go completely on the right the lower sprocket group and, as seen in the video, eventually creating a loop outside the capstan!

So, what's going wrong with the capstan motor?

Is the photocell group in some way related to this behaviour?

Flavio

Posted by Lee Purkis (Member # 2523) on February 09, 2013, 03:29 PM:

If the capstan pulls the film straight through and creates a loop on the right of itself after the roller i think the capstan motor might be running too fast. maybe someone messed about with the capstan speed control on the circuit board inside the projector

Posted by Flavio Stabile (Member # 357) on February 10, 2013, 08:55 AM:

Hi Lee,

Yes, I suspect that something is wrong in the electronic part of the projector.
I'm not so expert to solve by myself so I will try to have it serviced here in Italy.

I will update this thread as soon as I will have news...

Flavio

Posted by Ricky Daniels (Member # 95) on February 10, 2013, 09:33 AM:

Hi Flavio,

It's been a while since I owned a 708EL Stereo Projector but having just looked at your video it did remind me of the set-up.

It looks like the metal capstan pinch roller is running too fast and if I recall this pinch rollers speed is regulated by an optical sensor working behind the guide roller that is before the large take off sprocket. This guide roller should 'float' and as it moves to the left or right regulates the capstan pinch roller speed accordingly... (if I recall correctly). It looks like your capstan metal pinch roller is running at full speed and not getting any feedback from the ‘floating’ roller/optical sensor arrangement.
You may need to remove that final guide on the large sprocket and give the area behind this arrangement a good blow with a compressed air canister because something maybe 'blocking' the optical sensor. You may also need to remove the back cover of the projector and again give the area concerned a thorough clean. Failing that I think Ian at Perry's Movies maybe an expert or definitely Wittners in Germany

Good luck, I think it's a common problem and hopefully a good clean of ‘that’ area will cure this for you, otherwise you'll need to speak to Wittners who have spares.

OR you do not have enough pressure on the sound head plate that presses down on the film when the forward with sound position is engaged! This, if I recall is a mechanical arrangement that engages when you move the control knob to forward with sound and this could be the issue. Try applying pressure with your finger when you engage forward with sound and see if the floating roller floats as you apply differing pressure, if it does then maybe the problem is the sound head pressure arrangement.

Again parts are availablke from Wittners who were very helpful when I owned a 708EL STEREO projector.

http://www.beaulieu.de/pages/s8_wzub1.php?rubr=s8_wzub1

http://www.wittner-kinotechnik.de/katalog/00_home/index.php

BTW I liked the projector a lot, especially the perfect focus due to the picture head arrangement but found the lack of pulse sync an issue for me.

Best,
Rick

Posted by Mark Norton (Member # 165) on February 11, 2013, 01:19 PM:

Hi Flavio, Although I have not had this problem you have with my 708 EL Stereo, I have had a problem with the claw. Mine was worn and had grooves from pulling down on the film. Easy to check by running your fingernail under it. I just carefully filled them out and polished with a small stone.

Posted by Flavio Stabile (Member # 357) on February 11, 2013, 01:50 PM:

HI!

This afternoon I left the projector to the expert here in Rome, and from the very first inspection his thought went direclty to the capstan motor.
In sound mode it runs too fast and it's not even affected by the change of the speed (18 fps / 24 fps) and this is not normal...
He also excluded any problem related to the photocell sensor, due to the fact the moving the group with the loop sensor (that in my video completely moves on the right trailing the film) there are variations in the claw motor.

So it should be definitively a problem related to something that controls the capstan motor, but he will check in deeper.
It could be also out of regulation (let me pass this sentence) or worst a fault in the MCC 140 integrated.

Of course, once solved this he will need to check about the claw situation, if damaged or not.

Thanks to all and again and I will let you know as soon as I will receive further news (hoping good!).

Flavio

PS. One more thing.... Can anyone tell me if the Service Manual for the HTI version is available anywhere? OTC has only the standard manuanl for the halogen version... Thanks!

Posted by Flavio Stabile (Member # 357) on February 16, 2013, 12:45 PM:

Hi

today I received news from technician who is working on my Beaulieu and he told me that the problem of the capstan motor is solved! [Smile]

I have no details because it was just a phone call...

A good news... but there is another not so good! [Mad]

He is has experienced another issue... when the HTI lamp is striked on, pressing the button that creates the discharge, the entire panel with vumeters and the various lights becomes completely off and the sound disappears!

Does anyone know if there is some protection for the amplifier, probably with a relays, that intervenes during the strike, but for any reason it remains off?

Can anyone tell me where to get the HTI model service manual?

Flavio

Posted by Viktor Gibarti (Member # 1560) on February 16, 2013, 01:57 PM:

Hello Flavio,

You can ask the Björn Andersson from Sweden! He is the beaulieu God, very professional service man!!!
info@beaulieu-service.com

Viktor

Posted by Flavio Stabile (Member # 357) on February 16, 2013, 02:54 PM:

Hi Victor, I'll try to contact him, hoping to have a reply...

Meanwhile if someone has some idea based on his knowledge on this machine please let me know.

Thanks

Posted by Alan Rik (Member # 73) on February 17, 2013, 12:41 AM:

I can vouch for Bjorn. He is a wizard of the Beaulieu's. He has worked on 2 x 708 El Machines and one of them was an HTI. He rebuilt the entire ballast and ignitor. I feel he is the BEST Beaulieu technician. You are in good hands with Bjorn.

Posted by Ricky Daniels (Member # 95) on February 18, 2013, 03:44 AM:

Flavio,
Sounds like you are in good hands. Hope it's fixed soon.
Best,
Rick

Posted by Hugh Thompson Scott (Member # 2922) on February 18, 2013, 08:08 AM:

It's always best to let the experts sort things out, fingers crossed for Flavio.

Posted by Flavio Stabile (Member # 357) on March 02, 2013, 06:15 AM:

hi All,

my Beaulieu 708 HTI has finally been completely fixed and it works really great now!

[Big Grin]

Here below during a test...

https://vimeo.com/60773473

I'm so happy now!!!!

Flavio

Posted by Ricky Daniels (Member # 95) on March 02, 2013, 07:24 AM:

Good news... what was the problem in the end?

Posted by Flavio Stabile (Member # 357) on March 02, 2013, 08:27 AM:

He had to replace the CS 140 and the LC 200, if I remember well....

Posted by James N. Savage 3 (Member # 83) on March 02, 2013, 09:28 AM:

Very happy for you!!

Nice projector. Almost has a 16mm look to it [Wink]

.

James.

Posted by Flavio Stabile (Member # 357) on March 02, 2013, 12:23 PM:

Thanks James!
I'm really enthusiast of it!

[Smile]

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