8mm Forum: Burnt Lamp

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Posted by Grant Fitzgerald (Member # 2796) on January 31, 2012, 03:11 PM:

So I was so exited today because my copy of Mickey's Christmas Carol came in the mail. I set up my projector to watch it and right when I turned it on my lamp burnt out! What a terrible time for it to burn out! Just as I got the film I have been wanting for such a long time! So I ordered a lamp off ebay. Now I have to wait to until next week. Shoot!

Posted by Alexander Vandeputte (Member # 1803) on January 31, 2012, 03:20 PM:

Another lesson learned ! Always have at least one spare lamp around. Those things only burn out on crucial moments.

Posted by Graham Ritchie (Member # 559) on January 31, 2012, 03:33 PM:

Its probably as you say burnt out, but if the lamp looks ok try cleaning those lamp pins with a bit of fine wet/dry rubbing down paper and try again, plus, before fitting a new lamp I would suggest cleaning those pins before fitting so there is good contact and less chance of overheating at the point of contact due to resistance.

Graham.

Posted by Paul Adsett (Member # 25) on January 31, 2012, 04:12 PM:

That,s good advice from Graham. The other day I fired up my GS1200 and thought the picture looked unusually dim. Examination of the bulb showed that the contact pins were burnt and eroded so the lamp was getting far less than the normal 24 volts.
Unfortunately, the lamp contact design on the Elmo is just awful. You have round lamp pins sliding into spring loaded contacts which are flat, so theoretically there is a line contact of zero contact area!! [Eek!]

In practice of course there is a finite contact area, but it must be very small indeed, so eroded/oxidised contacts can really ruin the brightness of the GS1200. I have seen this many times with my GS1200 lamps, and I believe that in practice there is a constant sparking/eroding process going on which literally eats away at both the lamp pins and the socket contacts. Time to throw out the GS1200 socket and retrofit with the type that contacts the lamp pins all around, not just in one place.

Posted by Grant Fitzgerald (Member # 2796) on January 31, 2012, 05:50 PM:

Thanks for the advice guys!

Posted by Winbert Hutahaean (Member # 58) on January 31, 2012, 06:13 PM:

Grant, for emergency...go to a dollarstore. Find a 12v 50w which cost you $1. It will fit your projector (if your projector uses EFP) only it will be much dimmer.

Posted by Grant Fitzgerald (Member # 2796) on January 31, 2012, 08:20 PM:

This is the lamp I bought. I don't think it will work?

Posted by Winbert Hutahaean (Member # 58) on January 31, 2012, 09:30 PM:

Grant, if the two pins of both lamps are the same, why not?

I put this $1 lamp on my cheap projector to check my prints.

Posted by Grant Fitzgerald (Member # 2796) on January 31, 2012, 10:44 PM:

Because the pins on the one you recommended is on the back and not the side of the lamp.

Posted by Winbert Hutahaean (Member # 58) on February 01, 2012, 06:00 AM:

So it means your projector is not using EFP (12v 100w) lamp.

Posted by Grant Fitzgerald (Member # 2796) on February 01, 2012, 07:28 AM:

Right! That is why I didn't think it wouldn't work. [Wink]

Posted by Barry Fritz (Member # 1865) on February 01, 2012, 02:32 PM:

Hope you bought two from Ebay.

Posted by Grant Fitzgerald (Member # 2796) on February 01, 2012, 03:06 PM:

Why two?

Posted by Winbert Hutahaean (Member # 58) on February 01, 2012, 07:28 PM:

quote:
Why two?

Because 10 are too many [Big Grin]

... Seriously, I believe Barry meant you need to have extra for a stock.

Remember those lamps are rated for 50 hours life only. There is no rule that llamp will die after 50 hours. It can be 100 hours or more depend on many factors, e.g the quality of electric current at your place, how many times you are on and off, how is the cooler in your projector, etc.

So lamp will die eventually and you need a stock at least one before you are ordering the new ones.

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