Some time ago, I picked up an older styled Meade DS-115 telescope. It was a 115mm diameter reflector telescope, with a focal length of 910mm. While the model is becoming a little dated, it is a great telescope and the lenses are still crystal clear and the tracking motors work just fine.
The Meade DS-115 telescope also came with a Meade Autostar handset loaded with a starguide reference database to control object finding and object tracking. This is a handy device, but on its own is a little limited when compared to the experience offered by fully computer interfaced, graphical night sky mapping from modern computer software.
Unfortunately, the scope did not come with the optional computer interface cable that allows connection of the telescope to either USB ports or the older standard 9-pin (DB9 RS-232) serial communications port. This was despite the included Autostar handset having the required pinout socket on it’s base, ready to use.
Why make my own cable? Because buying a specialized cable for this telescope from Meade is relatively expensive…for just a cable. I therefore set out to find a cheap DIY option.
With relatively little effort, I managed to work out the wiring connections needed and make a suitable 9 pin RS-232 serial communications cable from spare cables and connector heads that were laying around. The interface cable changes the entire astronomy experience with this scope. It works fantastically. The cable allows full telescope support from a PC or laptop serial communications port. All tracking, object location and coordinate pinpointing can now be done with just the click of the mouse on any desired sky map object.
There were absolutely no details on the internet about DIY wiring requirements for this particular interface cable, so I truly hope the information I provide can help others harness the power of modern computer software in their astonomy.
The specific telescope was labeled as a 115mm (F=910mm f/7.9) scope manufactured in Taiwan, made to specifications of Meade Instruments Corporation of California, USA.
When I bought it, the telescope was a being sold for a ridiculously low price. I assume the previous owner simply thought it didn’t work. Hmmm ….. As we know, rarely does such a concept instantly register with an inquisitive and willful DIYer!
In reality the only real problem with the telescope was that the main mirror and internal lenses were just extremely (extremely!) dusty. After unfastening three small Phillips head screws at the end of the telescope barrel to access the main mirror and some careful cleaning with a soft cloth, the scope was on its way to getting it’s eyesight back.
After also cleaning all eyepieces and included lenses, I was totally amazed! This was a high quality telescope capable of amazing clarity. Views of the moon, planets and star clusters were impressive. Luckily, at the time of this project, Saturn and Jupiter were also both putting on a nice show.
The ease of modern astronomy however, really comes to life when any scope is connected to graphical sky mapping computer software. With “freely available” open source telescope software, the entire known night sky can be laid out on a computer screen and tracked in real-time. Connecting the telescope to such software provides the ability to pin point any object on the computer screen first, and then with the click of a mouse, automatically navigate the scope motors to that specific coordinate in the (real) sky. This is extremely handy when trying to find that beautiful but hard to find star cluster, or even just to get that last quick glimpse of the rings of Saturn for the night … (again, because they are so mind warpingly amazing)!
Should you wish to make the DIY Meade D-115 telescope interfacing cable I have mentioned above, I hope you too end up having as much fun as I did scanning the virtual sky to initially select viewing targets and then easily navigating to them in the real sky.