Film-Tech Forum ARCHIVE: Veronese (LX1600) Rectifier Problem

This is topic Veronese (LX1600) Rectifier Problem in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Andy Jenkin (Member # 8332) on 09-04-2017, 12:24 PM:

Hi there,

We have a pair of Veronese LX1600 portable 35mm projectors, however only one of the two rectifiers will strike either lamp successfully. The other one will power the projector fine, but cannot get the lamp to strike. When you power it on you can see the lamp pulsing every second or so, but it will never actually strike and maintain an arc, even when the current is at 100%.

It reminds me of a problem I had with an Irem N3, which was caused by the main relay not activating. The only relay I can see inside the rectifier, a 24V DC one on the main board, does seem to be working, as I can see the internal connections being made through the clear casing.

I can't see anything obvious, nothing burnt out, no bulging capacitors. Any ideas of what else to try? I'd really like to get this pair working!

Cheers,

Andy

Posted by Sean McKinnon (Member # 612) on 09-08-2017, 12:37 PM:

I might start by measuring the no load voltage if you know how to do that (be careful if you don't disconnect the igniter you can fry your meter)

It sounds to me like the igniter is firing without enough no load voltage behind it to establish the arc. I would check the mechanism used to signal to the igniter when the OCV is high enough (most likely a zener diode) and I would check any large capacitors.