SPECO LP-270: Feb./Mar. 1996 vintage (non-removable brain)

The platter runs at 'variac speed' no matter what the position of the payout control arm... Not a problem at the beginning of the movie, so most people won't notice that there's even a problem until later on in the show. Then, later on in the show, the platter runs too fast and causes a wrap.

It only happens with the top deck. It is an intermittent problem.

It happened on one show and we caught it in time and were able to monitor the speed and babysit it through the show. At the end of the show I checked out the whole platter and there was nothing wrong. About a week later, the problem appeared again and caused a wrap.

Although we are still using the platter system in that house, the top deck is under quarrantine until we can be sure it won't happen again.

What I checked:

1) Correct buttons pressed.
2) Payout arm not stuck. It moves freely.
3) No dirt or crap in the bearings.
4) No metal shavings and crap stuck to the payout magnet.
5) The payout magnet isn't twisted out of position.
6) The film break switch at the bottom of the Yo-Yo (variac) isn't stuck.
7) All fuses, etc. are intact.

Last two theories:

1) Payout control PC card?
2) Sticky switch in the control box? (I HATE replacing those switches! -- Please don't be a bad switch!)

Anybody have any suggestions?
 

------------------
"If it's not worth doing, I have allready been there and done it"
 

I have eight of these beast at one location and have very few problems with them. Don't get me wrong there not the best design ever but after 15 years and still running it could be worse. I think you may be on the right track. Where the magnet is located under the brain assy fastened to the front of the platter deck support arm is the payout control board assy. Part # 111-0021-03. This could be faulty. They are quite easy to swap out and will tell you right away if the problem is resolved. More often then not what happens is the magnet becomes misaligned with the payout control board. Not so much twisted as back and forth. Attaching the magnet assy to the payout control shaft is usually a philip screw, while holding the payout arm in the 3/4 position slide the magnet assy. back and forth as to piviot on that philips screw. This will take some time since the platter ***must be unplugged before each adjustment is made, (otherwise will will get a healthy belt from the board.)*** The idea is to have the magent adjusted so that it will engauge the motor when the control arm is at 3/4 position.
Good grief after re-reading this post I may have confused you more. Good luck...let us know how it works out. If instructions are confusing let me know, we may be able to talk through it on the phone.
 

------------------

 

The magnet is aligned 'sideways'...
If the yo-yo's down, (break-switch activated) the platter won't start up till the arm is about 1/4 of an inch from the left bumper stop. (As the manual recommends.)

If the yo-yo is up, the platter stops rotating when the arm is about 75% of the way towards the right bumper stop.

I never thought about moving the magnet in and out... I'll give it a check.

I still havent't checked the switches in the box, yet. It's kinda' hard to do during run-time. Friday morning after print build-up and before 1st show is usually the time I get to do stuff like this. I'll do it then. The big problem I have with this is that it comes and goes! Problem occurred, we baby-sat the show and when it was over we checked out the whole platter. It was okay. It ran okay for 3 or 4 days before it happened again. When I checked the platter out, it was all okay again. This is why I theorized that it might be a bad gang-switch. We've had a couple of them go bad before. (BOY! are they a BITCH to fix!) The last time the deck quit working all together. It was a burned contact inside the gang-switch. I can't see how that would have caused a platter to run at variac speed 100% of the time like is happening now. Maybe there's a "cat whisker" inside the switch box, causing a short somehow?
 

If the yo-yo is up, the platter stops rotating when the arm is about 75% of the way towards the right bumper stop.<<

Is that the same position of the payout for all three decks?

 

I put the yo-yo down. All 3 platters start running full-speed at 1/4" from the left bumper.

I put the yo-yo about 1/2 way up and taped it there. All 3 platters are full-speed @ 1/4" from the left, slow speed (as determined by the height of the yo-yo) in the middle, and all 3 platters turn off at about 75% of the way to the right bumper.

I changed the payout card in the top platter then checked and rechecked the magnet position.

I opened the control box, dusted it all out and checked all the wires and internal contacts that are visible. They are all good.

At this time, I still have it quarrantined. The reason is that I don't want to put it to the acid test on a Friday night. Come Monday, I'll try it out again and see how it runs.... News at 11:00!!!
 

I have, however put the word out that the person running that end of the bldg. is supposed to go check on that platter every few minutes until we're sure (reasonably) that there won't be any more trouble.
 

------------------
"All right, brain. You don't like me and I don't like you, but let's just do this and I can get back to killing you with beer." - Homer Simpson

 

ME: "Well, because it could actually SAVE you money in the long run."

Mgr.: "We've gotta keep our budget down..."

etc, etc, etc......
 

Thanks for the advice! Film-Tech RULES!