8mm Forum: st1200 light problem

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Posted by Gary Crawford (Member # 67) on October 28, 2005, 09:28 AM:

I was giving a show at the Library last night....had threaded up the st1200 for a couple of shorts before the main 16mm feature. I had run a few feet to focus,...had turned off the lamp for a minute ..then reversed the film to get back to the countdown, but when I turned on the lamp...nothing. I just thought I had blown a lamp, but it didn't look blown..,and when I put in a new lamp, same thing....nothing. Motor and drive working fine. Before I tear into this machine on my own, does anyone have any guidance to offer. I know there's a main fuse on the outside, but is there a fuse for the bulb circuit inside ? Could that be the problem? Any help will be appreciated.
Ps. I brought another super 8 machine with me and the show did go on.
thanks

Posted by Chip Gelmini (Member # 44) on October 28, 2005, 11:22 AM:

Hi Gary

You don't say what 1200 model you have, but I am guessing it is a D model. Check for condesnation and/or corrusion on the bulb prongs. Clean them gently with a pencil erasure or steel wool. Sometimes this will cause a short and the bulb won't strike.

There could be buildup inside the switch as well, without the bulb installed, just move the switch on & off a few times rapid succesion. If these tips do not help, then you need further repair.

Don't forget to check bulb connections in the wiring, a more envolved repair but not real serious.

Chip

Posted by Jan Bister (Member # 332) on October 28, 2005, 09:48 PM:

For what it's worth, (at least in my ST-1200HD and also an older ST-1200D that I have for parts), there are two fuses inside the machine below the transformer which are easily accessible after removing the rear cover.
Definitely check the bulb connector prongs first, though.

Posted by Gary Crawford (Member # 67) on October 31, 2005, 08:12 AM:

thanks for the advice. I don't think it would be corrosion on the bulb prongs...I tried two new bulbs ..same result. This week , I'll tear into it and check those fuses inside. the one I'm having trouble with is an st1200....the first model. no d no HD.

Posted by Kevin Faulkner (Member # 6) on October 31, 2005, 08:25 AM:

I'm not too sure that the lamp does have a seperate fuse. I think it's protected by the mains fuse which you can access externally.
The fact that the machine still runs means of course that the fuse is ok.
I think the suggestions above are good ones but it might be a faulty bulb holder or switch.

Kev.

Posted by Dan Lail (Member # 18) on October 31, 2005, 08:59 AM:

I had an St-1200 with a loose wire coming off the lamp socket. Thanks to Kevin I found it and secured the connection.

Have you tried a third bulb? Or check the bulb prongs with an ohm meter.

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