Very interesting read here
http://tech.groups.yahoo.com/group/ss2k/message/7076
Saying suppling any inverted A/C power into the Atlux / SS2K-PC be it the mount Mount or indirectly via an A/C powered PC via auto-guider cable into the hand controller can cause this - more investigation when the weather clears.
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ss2k@yahoogroups.com, "JAMIE FLINN" <jamiecflinn@...> wrote:
>
Have I got some info for you!!!!
I have been dealing with this for a few years and last month isolated the problem (at least for me)....AC current:
perform the following control test using a guide camera if you have one (reticle eyepiece if not)...all of this assumes you are using "house" power to some kind of 12v inverter...
1. hook up your system as normal - AC to inverter to ss2k - rs232 between ss2k and computer (also on house power) if you use that - there are various combos here to try
2. hook up your guider as normal
3. polar align - do 3 star alignment - make sure you are in polar mode
4. while watching the guide star slew your mount just a bit to make sure you know which way the star moves to be too fast (sidereal + whatever)....center your star
5. watch closely and make sure without touching anything you are seeing RA drift only (at least not massive dec drift because dec drift also induced ra drift)
6. *****very quickly, swap house power to the mount for a battery pack....turn on ss2k and press ESC (your 3 point alingment will still be there)
7. centre and watch the star again......if you see drift in RA still and have the computer attached via rs232 to the ss2k PULL THE PLUG on the computer (assuming laptop which has battery)
8. watch the star - at this point you may see the drift stop dead - it did on mine - I found that house ac connected in any way - even through a line filtering UPS (which made the drift slightly less but still there) -
I had drift - BUT NOT ALL THE TIME > This lead me to believe that the power supply to my house was subject to "sour power" - noise from airconditioners, electronics etc...
Once I switched to all battery power with no ac contact, I have been
steady as a rock. This problem also plagued me at StarFest every year
using the campground power - by the time the place was full and there
were fridges and fans and scopes and who knows whatelse, I would be
drifting almost out of control
Here are my combos
AC -> INVERTER -> SS2K = DRIFT
AC -> COMPUTER->RS232->SS2K = DRIFT
COMPUTER ON BATTERY->RS232->SS2K + SS2K ON BATTERYPACK->AC (AS IN CHARGING THE PACK) = DRIFT (I COULD NOT BELIEVE THAT ONE)
AC->UPS->COMPUTER->RS232->SS2K = DRIFT
BATTERY->COMPUTER->RS232->SS2K = NO DRIFT
BATTERY->SS2K (NO COMPUTER) = NO DRIFT
BATTERY->COMPUTER -> RS232->SS2K + BATTERY->SS2K = NO DRIFT
I also played with shielding every cable attachmednt to no avail....I now own a huge 60amp/h battery supply for my laptop and cameras, and use 30 amp/h battery packs for the ss2k and heaters