It's possible the X safety switch is not working.
John Hermanson
___________________________________
Camtech, Olympus Service since 1977.
21 South Lane, Huntington NY 11743-4714
631-424-2121 http://www.zuiko.com
Free Olympus Manuals: 1-800-221-3000
___________________________________
----- Original Message -----
From: <john@xxxxxxxxxxxxxxxx>
To: <olympus@xxxxxxxxxxxxxxx>
Sent: Monday, October 09, 2000 6:33 PM
Subject: Re: [OM] OM-1n flash sync problem
| On Mon, 9 Oct 2000 02:09:08 EDT, Tim wrote:
|
|
| >The following may help you diagnose your problem, especially if you know
a
| >bit about electronics!
| >
| >Background:
| > I don't have the official OM1N schematic but assuming it
is
| >similar to the the OM2N in so far as the flash is concerned then the OM1N
has
| >two sets of sync switches one for FP and one for X. The FP switch circuit
and
| >coaxial flash connector is isolated by a commonly available 1N400(6?)
series
| >diode from the X sync circuit. The X/FP selector either connects the X
and FP
| >trigger switch contacts in series (X mode) or shorts one end of the FP
switch
| >to ground (FP mode) It ony operates on the coaxial connector ** unlike
the
| >OM1**.
|
| I have a copy of an OM1 manual and, according to that, there is no
| diode isolation circuit (unlike the OM2). There are two contacts in
| series, the FP one "nearest" the socket and the X one to ground. In
| the FP/X switch is a simple shorting switch that shorts the link
| between the two contacts to ground when in FP position, and is open
| when in X position. When the shutter is fired the FP contact closes
| just before the first blind starts moving and remains closed
| throughout the shutter operation. The X contact closes as soon as the
| first blind is fully open.
|
| In FP position, the flash contact shorts to ground as soon as the FP
| contact closes and so an electronic flash fires too soon. When the
| switch is open (X position) the circuit is made through the FP contact
| but finally shorts to ground when the X contact closes. The manual
| specifically mentions a fault condition of poor insulation across the
| X contact so that the charge in the trigger circuit of the gun leaks
| away in the few milliseconds between the closure of the FP contact and
| the closure of the X contact.
|
| Unfortunately it looks as this may be happening in your camera. I
| would not have thought its repair would be too difficult, though.
|
| Regards
|
|
| John Gruffydd (Mold, Wales, UK)
|
< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
|