Fan Motor Tuning on Elmo GS 1200

[Thomas Knappstein]

Hello at all!

After modifying the Lamp to a 250W Two Base Pin Lamp in my Machine the Heat was coming up much more.
So what I´ve done is setting the Fan Motor Voltage up to 40V. Original it is running with 35V when the Main Motor and the Lamp is on.
Main Motor and Lamp are dropping all Voltages of the Transformer down a little bit. And the main Motor and Fan Motor are wired on the same Rectifier and the same Coil on the Transformer. Now I have made a little Board with Rectifier and Cap on it. And in the first Version I have swiched the Voltages by a little Relais on this Board. But in the final Version now I have a manual swich where I can set the Fan Motor from low to high. And I have spend the Fan Motor a little Conector. So I can take it out easier to lubricate the front Bearing. Here are some Pics of this Modification.

[Alan Gouger]

Very nice Thomas. Nice to see the GS had enough space inside to fit your new board. Do you notice a brighter picture with the new lamp?

[Thomas Knappstein]

Hi Alan!
Yes the Picture was much brighter because of focusing the Lamp in the Mirror. I have cut of the Back of a Philips 250W ELC Lamp and use the Mirror for the Osram two base Pin Lamp 24V250W of a Slide Projector. But this Lamp need much more Amps so you can´t use the internal Elmo Transformer. The transformer from a Slide Projektor can be used. Graham Ritchie has done this with his GS too. On the Top of my machine i have a little box where the Lamp Conector is inside. The little Swich for the Fan i have put in there too. Here is one Picture of my Lamp modification.
Last Time many People have modded their machines to the Xenpow HID 150W. But I think the soft Halogen Light must stay to Super8 for the right Athmophere.

[Alan Gouger]

Thank you for the extra details Thomas. Now I understand better what you have done. I have heard good things about this lamp. In your picture it is hard to see the mirror, can you provide a little more detail or provide another picture. So you are running an external PS/ballast? I have converted a few projectors using the Xenpow, the color spectrum shows a spike in green and yellow, red is under saturated. The results from your mod should be more pleasing. Thank you for posting this, I hope it inspires others to give this a try.

[Thomas Knappstein]

Here are some Pictures from the Mirror. It came from a 24V/250W ELC Halgen Lamp. You also can use one of the original ESC 200W Elmo Lamp.
I have cut the Socket with the Bulb by a Diamond cutting Disc. The Lamp Holder is original GS 1200. I´ve moddet it for holding Mirror and Lamp Conector seperate. So I can move the Lamp in the Mirror forwards and backwards to focus the Beam to the Super 8 Frame. The external Transformer is a normal Halogen Transformer with 400W. I put it in a seperate Metal Box with Ampere Meter. And you can see the Difference between the 250W Cold Mirror Bulb and the 250W Two base Pin Lamp.

[Alan Gouger]

Thomas, if searching to purchase that lamp is there a part number to differentiate it from the typical GS 24v 250watt bulbs that don't require a beefed up PS. Thank you for the additional pictures and information. I always wondered the best way to remove and open the rear of the quartz reflectors

[Thomas Knappstein]

The Part Number of the Bulb is OSRAM 64655 EHJ 24V/250W.
The Philips Type where I took the Mirror from is Type 13163 ELC A1/259 24V/250W.