115 volt to 82volt???

[uvodee]

pics before from the result with 2 LOA's in one enclosure with simple aluminum foil glued against photoboard that was shaped as a cone...

I was trying to explain (2 years ago) that the results where truly very good.
no one took my route when some of the guys failed...

but that was then, this is now, the fxl bulb will give even more light than the LOA and as I can see this result does not need any real reflector , maybe a crude rear shield but that's all.
The front lens will be the most crucial thing to think about but as usual I want to come up with ideas that have not been milked out!!!!!

J-P
here is oneof the pics I saved from 2 years ago , IKEA enclosure and 2 LOA's

[uvodee]

picture , the result o a first power up , the light coming out of the enclosure was so overpowering that, when I took a picture, the room looked dark and the brightness coming out of the projector lens was overpowering the other lights in the room

J-P

[tbates57]

Hopefully, this info is not too stale to be useful.

My Apollo Concept overhead projector uses either en ENX (360W) or FXL (410W) 82V bulb. The power supply circuitry includes only a P1000J silicon rectifier (600PVI, 10A) in series with the lamp and line and a P6KE400CA transient voltage supressor (400V, 600W) in parallel with the bulb (of course they're switchs, cooling fan, and a thermal breaker).

The earlier post of how the rectifier drops the voltage was very helpful. I think the TVS helps to control the initial surge. These two devices should be fairly readily available at under $1 each.

[Deimok]

can anybody post a circuit diagram on the setup for nocking down the voltage? I took ac/dc theory 12 years ago and cant remember a damn thing! Please Help!

[Guy Grotke]

It's all in the previous post! If you can't figure it out from reading that, then you have no business playing with 120 VAC circuits. Here's what I would suggest:

Buy:

1 silicon rectifier (600V, 10A)
1 surge supressor (400V, 600W)
1 lamp socket to fit your bulb
1 SPST switch (120 VAC 10A)
1 fan (120 VAC)

Then take the projector, parts, and a printout of the post before yours to an electronics technician or electrical appliance repair shop to have them wire it for you.

No mistakes, no house fire, no electrocution, no law suit...

[Deimok]

I decided to go with the dimmer circuit. It was the quickest and cheapest method possible. I used a multimeter to set the corrected voltage on the dial and placed a screw there with a screw on the knob. This makes is almost impossible to spike the voltage to high.

No I didnt electrocute myself!

[victor-eyd]

uvodee,

what dimmer did you use and can you show us the diagram. I have an fxl setup myself and would like to try your approach

Victor

[uvodee]

a bit off the diy, altough i still use my black out cloth screen.

I bought the dimmer at IKEA





they sell more of them in a week than Lowes and HomeDepot combined in a year!

[victor-eyd]

uvodee,

Thanks for responding. is this the dimmer you bought and do you have a wiring schematic for the fxl mod?

http://www.ikea.com/us/en/catalog/products/10063148

Victor

[modgod]

how exactly are you powering the FXL bulb? are you you using mains power and stepping down the voltage, or are you using the original powering system from an actual OHP?

any idea how big the step down transformer and other parts that power an OHP bulb are, I want to have an idea of whether or not I'll need to externalize the powering circuits if I'm gonna be replacing my retail projectors bulb with an FXL.

thanks