Having got the backend of the 60mm finder swapped for a guider adapter the next job was to sort an EQdir replacement for the SynScan hand controller. Initially I thought I’d use an FTDI serial-TTL cable but I’m short of USB sockets on the Asus Netbook and I want to connect my bluetooth GPS receiver as well so I went looking for a wireless solution. Hobbytronics sell a suitable bluetooth module and I found some example circuit diagrams on the EQmod website so set to work with a soldering iron. Here’s the end result, prior to boxing up:
Testing revealed no problems so I put it in a small plastic project box and it hangs off the mount’s DB-9 connector.
The next problem was some star elongation I noticed when imaging NGC4244 on friday night. Initially I thought it was field rotation, but a closer look showed that the elongation was in the RA direction. While the guide log showed both axis having less than 0.5 pixel errors, RA was considerably worse and was bouncing between +/- errors. Next time out, I reduced the aggressiveness of the RA guide corrections and with a setting of 0.4 the problem was much reduced. As I previously mentioned, I’ve got a sizeable unbalance in the RA axis while I wait for a replacement counterweight so hopefully, this is the root cause of the problem.
Here’s the result of the tuning. 13 frames of 5 minutes each of M97 & M108 in Ursa Major.
Telescope: Zenithstar 70
Camera: QHY9C