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Wednesday 9th Heavy overcast, windy and raining. Better find something useful to do. Instead of waiting for a sunny day!
It occurred to me that I could check the Dec drive ratios by slewing from the eastern horizontal parking position to the western horizon. I did not connect the computer. Just AWR and IH2.
I read the coordinates off Skycharts/C-du-C and entered them as slew coordinated on the IH2 handset. The telescopes started slewing but stopped on the meridian as always. How to turn off this pause at the meridian? I am always present during Goto slews. So there shouldn't be any danger. Should there?
Repeated stalls so I checked the telescope balance again. Dec. Dir. has changed to Positive again. Manually reverted to negative.
Manual slew 180° Dec only. Stalled so had to re-check balance and worm adjustment. Telescopes stopped at the Meridian and then ran backwards on the Simple handset. It is supposed to be self correcting at the Meridian.
That's odd! I slewed manually and [visually] it never reached the western horizon. Showing 0 on the IH2. That sounds like its drive ratio setting is low. 2° short of a full Dec slew. I have set the OTAs horizontal on the paddle and shall hit Home for slewing back to the eastern horizon. Now it won't start the slew! Inhibited by being below the horizon?
Manual: Slewed correctly 180° in 3m50s and stopped at horizontal east. IH2 showed correct altitude.
Goto W horizon: Did not stop at Meridian this time. Landed correctly! Whoopee?
Home: Passed the Meridian safely. Stopped high. Tried to adjust on the paddle. AWR showed Crossed Meridian. Then the IH2 handset stopped responding. Power off to reboot.
Goto W from Home. Okay. Return to Home. Okay!
Whoops! I forgot to check that the slew had stopped at Home. I'd gone on a browsing trip about telescope drives. Then my wife called me in for dinner. I looked up and the telescopes were pointing straight downwards at the floor! The Dec drive was still running at a medium pace. It has never done that before. I may need an observatory assistant to keep and eye on the telescopes for me! I shall never leave the drives running while absent. Let alone absent minded!
Just when you thought it was safe: I went back over to the dome after lunch to continue testing the drives. Whereupon I promptly sat in a puddle in my plywood seated, computer chair. [Ikea] The dome has never leaked on the north side before. I glanced up and all the [doubled] ribs are now leaking. Grr! I am close to liking the idea of a GRP coating. I was unable to find any tarpaulin in sage green. Too late for polyester resin now!
The drives worked some of the time but stalled at others. A stall seems to be read as continuing motor rotation but with added noise. Whereas the motor is actually stationary. Which causes the slew to end prematurely but showing a completed slew reading. There must be some residual asymmetric imbalances with the dual OTAs. I ned the dome open to have enough light for safely freeing the worm housings from the wormwheels. The rain has stopped. I returned indoors just as the sun came out and the sky turned blue! Nothing to see on the sun! Grr?
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