HEQ5 pro mains power solution.

[scott maloney]

Just moved up from my skywatcher star adventure and recently acquired a secondhand HEQ5 pro. I'm looking for a power solution, temporary and then more permanently. I have a 12v 6a Laptop PSU you lying around which I was hoping to use just a test the mount for the moment with the idea of buying a car jump starter power for more mobile use. Just wanted to ask would both of these solutions work for me? see photo

[pete_l]

When I started with my HEQ5 I had it connected to a 12 Volt laptop supply. Just using the hand controller was fine. But when I had the controlling mini-PC connected to it via a commercial serial cable it became unusable. I had terrible trouble with "wild" slews, slews that mysteriously stopped, random movements - you name it. In earlier times the diagnosis would have been that the device was possessed.

By using ASCOMs serial debugging, I could see that frequently the commands sent to the mount were getting corrupted or were just downright gibberish. By process of elimination, I discovered that substituting the mount's power supply for a 12V car battery made all the problems go away - as if by magic.

Some web searching turned up a theory that the circuitry in the PSU that is supposed to filter interference from the switched mode power supply was the culprit (I don't recall the details). I built a transformer based power supply that used a linear regulator (7812 family) and I've never had a problem since.