Re: [APML] ST-4 and the Northern lights

[steve banbury <banburys@sonic.net>]

Hi John--thats an odd one!
At first blush I wouldn't think you could blame the symptoms on dirty mains as
the ST4 uses some
flavor of wall wart transformer to step the 120 VAC down to 13 ish. I believe
this is then rectified and post
regulated in the ST4 power supply.  

Doesn't help explain the symptom much I'm afraid.

Steve 



At 10:30 AM 10/31/03 -0500, you wrote:
>Greetings,
>
>I know I'm not imagining this...
>
>So last night I was preparing for an all night imaging
>session when the northern lights flared up (in Bedford, NH),
>so I rushed up to an open field, snapped about 30 or so photos
>over the course of an hour, then went back to my observatory
>to continue with my setup procedure.
>
>When I finally got on my target (NGC7K) and acquired a guidestar
>with my trusty ST-4, I went to do a calibration and nada, nothing,
>the guidestar wouldn't move (thus the x,y readout didn't change).
>I fiddled with cables, reboots, etc... for about another
>hour before giving up, I just simply couldn't get that x,y
>readout to change (I could get it to change manually by using
>the keypad on the lx200).  Flustered, around midnight, I went
>back to the observatory to retry, and whaddyaknow, the calibration
>worked fine.
>
>Now a similiar failure happened sept 7th, 2002, the night of the
>last big aurora here in the northeast.  I know that the ST-4 is
>finicky about power draw and I know auroral activity can wreak
>havoc on power grids... is this just coincidence that the two
>times my ST-4 has let me down were nights with auroral activity
>or is the inability to calibrate a manifestation of 'dirty' AC
>power?
>
>Puzzled in Bedford...
>
>john
>
>
>John Lanoue
>Principal Software Engineer
>Bedford, NH
><http://www.geocities.com/johnlanoue/>http://www.geocities.com/johnlanoue/
>
>_________________________________________________________________
>Fretting that your Hotmail account may expire because you forgot to sign in 
>enough? Get Hotmail Extra Storage today!   
><http://join.msn.com/?PAGE=features/es>http://join.msn.com/?PAGE=features/es
>
>_______________________________________________
>Astro-Photo mailing list
>Astro-Photo@seds.org
><http://seds.org/mailman/listinfo/astro-photo>http://seds.org/mailman/list
info/astro-photo
>  

_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo