8mm Forum: Vintage Kodascope 8mm projector that need lamps

This is topic Vintage Kodascope 8mm projector that need lamps in forum 8mm Forum at 8mm Forum.

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Posted by Clinton Hunt (Member # 2072) on June 29, 2010, 05:40 PM:

I have a Kodascope Eight model 60 (8mm projector) and it needs a 33 volt, 100 watt, T8, cande-labra bayonet base,all I can find online so far is a 20 volt.For a substitute do I need to install a lamp with a lower or higher voltage? Or can I use a different watt?. Cheers,Clinton

Posted by Steve Klare (Member # 12) on June 29, 2010, 09:36 PM:

The volts is what the volts is.

If you install a 100 watt bulb of lower voltage rating you'll blow the bulb and maybe the machine too. If you install a 100W bulb of higher rating it will get very dim very quickly as the rating gets higher than the machine's supplied voltage. For example a 100W, 40V bulb put on a 20V line will squeak out only 25W (really even less...)

I saw the same results you saw for that bulb:

http://www.donsbulbs.com/cgi-bin/r/b.pl/byd%7c20v%7c100w~ansi.html

Are you sure about that 33V?

Posted by John W. Black (Member # 1082) on June 29, 2010, 09:46 PM:

According to the GE lamp guide,this machine,if it's a Model 60T,takes a BYD bulb.You can get them at interlight@mail.com for $19.00. This place has all kinds of rare bulbs and great prices

Posted by Steve Klare (Member # 12) on June 29, 2010, 09:56 PM:

Hiya John!,

Yes, that's what I saw too. BYD is a 20V bulb.

Substituting projector bulbs is complicated business. The bulb's electrical specs need to match up with the power supply coming into the socket. The size and shape need to match up with the mounting scheme. The base needs to mate with the socket. Even if you have all that stuff right and the filament doesn't line up with the optics the picture will be no better than dim.

Posted by John W. Black (Member # 1082) on June 29, 2010, 10:11 PM:

Might have been the wrong bulb in there to start with.

Posted by Steve Klare (Member # 12) on June 29, 2010, 10:19 PM:

I thought that maybe the 20V bulb was for the North American market because our line voltage is 115VAC instead of 230, but the proportions don't work right: at that rate a 230VAC machine should use a 40V bulb, not 33.

Posted by Clinton Hunt (Member # 2072) on June 30, 2010, 12:36 AM:

Hi guys,thanks for the replies,I don't have the original lamp for the projector,I bought it off Trademe like that, I got the lamp info from the owners manual that came with it,it is the Universal model,I went to the website given here donsbulbs.com and found the 33v 100w lamp (BZG/33V/100W ANSI) - expensive tho...but will it work?

Posted by Steve Klare (Member # 12) on June 30, 2010, 08:13 AM:

The best thing would be to poke a voltmeter into the socket and see what's really there.

I would expect the reading to be a little higher than the normal lamp voltage. Let's say you see 35V (or more...) I'd bet it's the 33, since the meter wouldn't load down the power supply, but the bulb would.

If you see 23V(or more...), obviously it's the 20.

On the other hand, it's pretty safe to trust the manual.

Don's Bulbs is an excellent resource, but he is a little pricy.

The neat thing to try for obsolete bulbs is E-bay. Very often somebody gets a truckload of new old stock and uses E-bay to clear it out at pretty reasonable prices.

Thusly:

BZG Projection Lamps on E-bay

(North America only: sorry)

or:

More BZG Projection Lamps on E-bay

You can't lose at this rate!

If you know the voltage is 33V for certain it might be a good idea to buy several.

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