Cinerama Servo amplifier

[Bill Ryan]

The lifting arrangement was only installed later for the features which also only ran at 24 FPS not 26 FPS as the earlier (travelogues) did.

[Mark Gulbrandsen]

I like the under-slung feed magazine, Mark. The projectionists didn't have to risk pulling a back
or shoulder muscle slinging those big reels up to a feed spindle on top of the projectors. I Wish
I'd had something like that for the 70mm "Licorice PIzza" run last year!
(My feed spindles here are 7ft above floor level. Reel 4 (over 60lbs) was really a b-tch! )

BigReelPic.jpg/

Yea, no kidding! That's a ways up to be lifting that much film.

The Cinerama lifts I saw in Salt Lake City were made out of screw type garage door openers. I assume all of them were the same...

[John Eickhof]

hey Mark, speaking of Dennis, you ever hear how hes doing? and Clayton? i have a cinemiracle promo hard cover book with info on Dennis dad i thgink it was a way less elaborate but effective large screen system, and all the reel lifts i have seen were a vertical acme thread set up with stop limit switches and a simple pivot that would swing the reel into alignment with the feed reel shaft and the operator would simply slide the reel in place swing the arm away and place the keeper. the san diego cinerama had these still in use back in the 80s, i know of a couple theatres that used them to load reels on the cinemeccanice towers too up in montana...

[Mark Gulbrandsen]

hey Mark, speaking of Dennis, you ever hear how hes doing? and Clayton? i have a cinemiracle promo hard cover book with info on Dennis dad i thgink it was a way less elaborate but effective large screen system, and all the reel lifts i have seen were a vertical acme thread set up with stop limit switches and a simple pivot that would swing the reel into alignment with the feed reel shaft and the operator would simply slide the reel in place swing the arm away and place the keeper. the san diego cinerama had these still in use back in the 80s, i know of a couple theatres that used them to load reels on the cinemeccanice towers too up in montana...

Dennis is doing fine, as is Jon. I think Clayton is spending most of his time up at Bear Lake... According to Dennis as he used to travel with his dad doing the setups.... It took them two to three days to do a temporary installation. Not sure there was ever a permanent install of it because Cinerama bought it out basically because it was considerably better and it needed to be snuffed less it damage Cinerama's income. I never ran into the Cinemeccanica towers in my jobs across Montana... thankfully. I hate the things. The only acceptable tower I have handled is made by Ernemann.

[John Eickhof]

some of the carmike houses (former toi out of colo) had them along with v5s and v8s the only thing i thought was cool was they held two sets of reels and rotated to feed 2ndfeature while first feature was rewinding...of course the 3ph motors and starters were a royal pain! hope you are doing well, im going to seattle in jan for final testing and typing, hopefully a transplant is in my future! happy holidays!

[Mark Gulbrandsen]

Hi John, Yea... that was a nice feature of them. The Ernemann could only hold one set of reels. But it operated so smooth and reliably because it had DC servo motors. It was also more like a Double MUT. I hope things go well for you, keep me up top date on what's happening. I just have a left knee replacement left to get done and that should happen right around next September, or the second Kidneyversary.. Then I can work at getting back to normal. I still have 483 waterfalkls to check out in this State!
The image is of some of the parts I had to acquire to put the three Cinerama heads back into use again, But as 3-D projectors for a new system that Chris Condon was working on.

[Bill Ryan]

9A658B92-42C7-4892-9BAC-BF9488B6A788.jpg To bring things back on topic this is the servo amplifier.

[Bill Ryan]

AA75BA6C-043E-4E31-932C-270070B94556.jpg And the underside

[Bill Ryan]

Hi Guys,
I am looking for some Cinerama reel lifters.
Cheers
Bill.

[Mark Gulbrandsen]

Hi Guys,
I am looking for some Cinerama reel lifters.
Cheers
Bill.

What ever happened to that 3-strip Cinerama system that was installed in a guys back yard some where near you? I have pictures of that some place.

[Bill Ryan]

Hi Mark,
You are talking about John Mitchell’s gear l assume. I now own that gear. John said that
he had corresponded with you.
Cheers,
Bill.

[John Eickhof]

i would love to see a schematic of this unit...the 6sn7 was a great pre-amp and driver amp, it is a dual triode that under correct conditions would output close to 5 watts, the 6sl7 was also a dual triode with a comparable output range I would think it was a line amplifier for the control winding voltages in the selsyns probably due to the line loss and draw of early selsyns, like I said before the later 55 volt secondary selsyns were more robust and drew less current on the secondary side thus more could be paralleled in a circuit.

[Bill Ryan]

Hi John,
I think the 6SL7 drove the advance retard motor on the advance retard gearbox. Via the
change over relay which you can see on the back of the amplifier chassis. The whole thing appears
to reference the 1 phase mains input to the relative phase of the selsyn transformer.
By the way if I do find the circuit elsewhere I am
happy to publish it here.
Cheers,
Bill.

[Mark Gulbrandsen]

Hi Mark,
You are talking about John Mitchell’s gear l assume. I now own that gear. John said that
he had corresponded with you.
Cheers,
Bill.

Bill, Is that system still functional?

[Bill Ryan]

Hi Mark,
No it has been dismantled. By myself and I have had to relocate it into storage. Moving it all has been a mammoth undertaking. Plus all his film!
Cheers,
Bill.