gordtulloch

My Meade DS114 Telescope

Picture of Meade DS114

When I decided to replace my 13.1 Dobsonian with a GOTO scope, my first choice was the Meade LXD55 10” Schmidt-Cassegrain telescope. It was large enough aperture that I was pretty sure it would satisfy me for some time and included full GOTO capabilities yet was also mounted as a GEM so it wouldn’t suffer from issues that plague altaz designs, particularly field rotation. However, the cost was prohibitive at this point (my budget was pretty much $1000 since thats what I got for my 13.1” components), so I decided to get something inexpensive yet had an Autostar GOTO system and was compatible enough that any work I did on computerization wouldn’t go to waste. So, I picked up a Meade DS114 Altaz GOTO scope and Autostar #495 controller on Astromart for approximately $500 delivered from a Toronto amatuer who was getting a LXD55.

On receipt of the scope I was pleased to note it had pretty much already been assembled, so actual assembly took half an hour. Initial inspection confirmed that the scope was pretty much “department store” quality (this scope is sold in the states at Walmart) but this was not unexpected. Generally quality fit and finish was acceptable, as were the optics.

The first night out under the stars confirmed that the optics were properly aligned even after shipping (a good sign - collimation of my 13.1” was a neverending pain) and that they were of good quality. The scope easily split several doubles and picked up M13 and M31 no problem (although obviously much fainter than in my 13.1”) The GOTO functions were not very precise but I attributed this to the hasty alignment I did on the scope and my lack of experience with the scope. So far I was pleased, and went inside before the mosquitos drained me entirely of blood. Note to self: fog before going out next time. Another note: mosquito repellent with 95% DEET melts plastic telescope pieces! No real damage but glad I didn’t touch the Autostar screen.

Second night out was less successful - numerous attempts to more accurately line up the scope failed, apparently due to some slop in the aximuth gearing or motor. Another early night, didn’t see much of anything. Back inside, tried to update the firmware on the scope, not much luck attaching to the Autostar with a home made cable. Later found out that the version of the Autostar I had needed to be put in download mode specifically so pilot error strikes again - once I found this out everything worked swimmingly. Connecting the Autostar to my Dell Inspiron 3500 laptop and using Cartes du Ciel
The next day I took apart the azimuth gear assemblies and applied some fixes per the Meade manual to tighen things up. Also did some calibration of the drive system and training of the altitude and azimuth motors with a laser pointer.

Over the next few weeks sky conditions were poor - clouds every night with clearing sometimes in the wee hours, too late to go set up. In the meantime, I decided to replace the rickety tripod that comes with the scope with a temporary pier consitructed of 4 2x4s screwed together and an adjustable platform on top with 4 threaded rods to allow fine adjustment of height. In future I hope to make this part of a permanent observatory.

Finally, skies cleared and I was able to take things out to play - I also got a Steve Mogg universal webcam adapter which mates up my 3COM HomeConnect webcam to my telescope as a prime focus imaging device (prime focus means using the telescope as a telephoto lens with no eyepieces in the middle). I connect this to my Dell Inspiron 3500 laptop and use software named K3CCDTools to take AVI movies of objects which can later be stacked to simulate long exposures - this is a poor man’s CCD imaging setup that has resulted in some nice pictures for other people, so I’m eager to try them. Here’s a picture of the whole setup, new pier included.

DS114 complete setup

Alas, my third night out with the scope went similarly to the second one - I was trying to image the Moon and although I got the scope slewing to the right part of the sky, for some reason it wasn’t tracking, so the image of the moon slid out of the field of view quickly - to do imaging you need the telescope to track the object. Another frustrating night, and the next one too - a little bit of research and EUREKA! These scopes do NOT react well to power problems, either too little amperage or noisy power supplies. The telescope seems to work well on fresh batteries but not on the Radio Shack 800 mA power supply I bought for the scope - my bad, probably need 1.5mA or better (this seems to be the consensus in the various Meade forums I read on Yahoo Groups. (Later) Yes, indeed, the problem was power - the battery pack makes a ton of difference. No problems at all, alignment goes smoothly, and GOTOs are pretty darn close. I got some nice pictures of the moon. All in all, a great scope for the money!

All good things come to an end so this scope eventually got sold to fund purchase of a Celestron 8" F10 SCT!


All material Copyright (C) 2002 by Gordon Tulloch ALL RIGHTS RESERVED