Just FWIW on an old thread, all of the electronics for the LX200GPS-16 are still available from Meade. I own a LX200GPS-16 and work on a number of others for the Onizuka VIS on Mauna Kea, Windward Community College on Oahu and others. The mounts are solid (I didn't say precise) and the electronics are easy to repair. And a retrofit with Sidereal Technologies or Software Bisque TCS are common. And in 20 years there will certainly be other drive retrofit systems available to upgrade again, when the time comes. There is a lot of space in the big, hollow fork mount for future changes and modifications.
An important upgrade to the Meade worm drives would be to replace the existing lubrication with a 3:1 blend of Lubriplate 105 and Nye Fluorocarbon 868H damping grease. That will reduce friction, wear and noise. This is very similar to the formula currently used by a number of premium mount makers.
The advantage of Alt-Az over polar is that the eyepiece doesn't move around a lot and is more convenient for access by the general public. The Onizuka VIS uses adjustable-friction, rotating 2" SCT thread adapters that allow a standard 2" diagonal to be easily-rotated to different angles for different viewers. They are made by Starizona. I machined a 4" to 3" SCT thread adapter for them so they could use the 3" C14 adapter on their 4" port on their 16.
I would also suggest getting some newer, wide field eyepieces and get rid of the junk eyepieces I looked through on my visit in November. Broken, trash eyepieces give trash views. What an embarrassment.
And it would be nice if someone were to invest in getting the mechanical drive system repaired on the Schroeder refractor. It likely only needs to have its mechanism cleaned and relubricated but apparently it ground to a halt about ten years ago and still isn't fixed? What a shame. There are probably at least ten camera repairmen in Sydney that would be perfectly-capable of repairing that clock mechanism. Another option would be to put a simple gearhead servo motor and microcontroller directly on the RA worm gear and bypass the old clock mechanism. That could be done with minimal modification to the mount and would likely be fully-reversible in the future, if desired.
It would also be nice if the docents had a proper foundation in astronomy. For example, have them stop telling the public that meteors burn up because of friction. It is the rapid compression of gas in front of the object. PV=nRT.
I am a consulting observatory engineer that works for the observatories on Mauna Kea and others around the world. The Sydney Observatory is an incredible, historic observatory that with a few fixes and improvements, could be doing fantastic outreach. Unfortunately that doesn't seem to be happening right now.
