8mm Forum: RCA Model 416 - Lamp replacement

This is topic RCA Model 416 - Lamp replacement in forum 16mm Forum at 8mm Forum.

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Posted by Patrick Flynn (Member # 5615) on November 29, 2016, 11:58 AM:

Hi all,

Sat down last night to watch my new print of James Cagney's "Run For Cover" last night when the outlet shorted out, and I believe burnt out the bulb.

Now the manual I found on film tech is for the RCA 400 series (of which this was the last model) but nowhere in the 100+ pages does it explain the lamp housing, or how to properly remove, or even check, to see if a bulb is still working.

Any help would be appreciated. Thanks.

Posted by Barry Fritz (Member # 1865) on November 30, 2016, 06:20 PM:

Chrome knob on top side of center panel. Turn knob and pull. Panel will tip out with lamp inside.

Posted by Patrick Flynn (Member # 5615) on November 30, 2016, 09:35 PM:

Hey Barry, thanks for getting back to me. Yeah, I've gotten that far. But it's about the physical action to remove the lamp. If I twist it, the bulb loosens ever so slightly, but it doesn't give an inch. I don't want to pull it straight out (like my 8mm projector) because I fear it will rip in two. Do I have to take out the metal housing its encased in or... ?

Thanks.

Posted by Barry Fritz (Member # 1865) on November 30, 2016, 10:43 PM:

You need to press down on the lamp and then turn it. With most projectors you turn it counter clockwise. It is usually about a quarter turn.

Posted by Patrick Flynn (Member # 5615) on December 01, 2016, 12:48 AM:

That did the trick, Barry! Now, would a regular ohm meter be able to give me a reading on the current bulb as if it's still usable? Also, where would I find the type of bulb to replace it, should it need replacing? Thanks again, sorry for all the questions. Still learning. I'm much obliged.

Posted by Barry Fritz (Member # 1865) on December 01, 2016, 09:25 AM:

You should be able to check continuity with a multi-meter. Use the multi-meter to check voltage to the bulb socket also. I have bought most of my replacement bulbs on Ebay.

Posted by Maurice Leakey (Member # 916) on December 01, 2016, 09:43 AM:

Patrick

As Barry says, you can buy lamps on eBay. Many sellers are featured.

Your projector probably uses the pre-focus lamps which many early projectors were fitted with. Mains voltage for USA.

Usual fitment was a 750 watt for general use, this is coded as DDB. For bigger screens in schools and similar auditoria a 1000 watt can be used, this is coded as DFT.

Posted by Patrick Flynn (Member # 5615) on December 01, 2016, 01:18 PM:

Thank you both for your help. I bought a multimeter, and it turns out the bulb holds no charge. Took your advice and purchased a few on ebay for relatively cheap. How do I check continuity on the on the bulb socket - the same as I did for the bulb?

Posted by Barry Fritz (Member # 1865) on December 02, 2016, 01:01 PM:

You need to have the mains power turned on to the lamp position. Set your meter to test voltage. Then CAREFULLY touch the red probe to the contact in the bottom center of the socket. Hold the red probe there and touch the black probe to the metal on the side of the socket.

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