Re: Bluetooth and SiTech
Since Don W’s last visit we installed RF chokes “all over the place” and also put in a stick computer on the back of the telescope. We eliminated the plastic hubs as well. So, at this point we have a configuration that can be run remotely from anywhere in the observatory and it works. We also have an A/B switch installed near the remaining hub which allows us to switch between the original computer and the stick at the touch of a button. So we now have two computers that can be used interchangeably to drive the mount.
There are more no “call Dan” errors, no encoder errors, no MaximDL freezes, no computer reboots. The stick computer is connected to our “never fails” hub by a 28/24 high quality USB3 cable about 1 foot long. There is a 15 foot USB 2.0 cable of dubious parentage that one of us (Bob) “found” that goes from the remaining “industrial” hub to SiTech, through the mount. The last two nights I’ve been out there we’ve gotten a specific error “Bad Communication” and the mount stops. I’ve been able to clear that error by rebooting the SiTEch box and/or switching computers. Since I’ve gotten it using both computers, and the only thing that they have in common is that cable that Bob found. I conclude that cable is the problem. It even has an RF choke on it at both ends.
Given all that it seems to me that we now have a stable configuration except for this one cable. To me the easy and obvious solution has been to either run a serial cable to SiTEch through the mount or to buy a blue tooth adapter. I personally think that the more USB wiring you have, regardless of quality, the more trouble you will have in an outdoor environment. We have a second configuration in the observatory – a Paramount. It’s longest USB cable is maybe 6 feet long. It has never, in the four months it’s been there, experienced any failures at all. It runs off another Stick computer (or a laptop) located within inches of the mount. I also have a portable setup that I run in my back yard. Same deal – only short cables – longest cable is 6 feet. Again, NO USB problems.
The BT adapter seems really elegant to me. It sounds, though, as if there aren’t many of these in the field so maybe the serial cable is a better idea. My car’s phone seems to work really well J on blue tooth, as do my wife’s headphones. That’s all from me folks.
From: SiTechservo@... [mailto:SiTechservo@...]
Sent: Wednesday, December 21, 2016 12:50 PM
Subject: RE: [SiTechservo] Re: Bluetooth and SiTech
I believe initially we started with USB2 and decided to go 3 when we had issues thinking that 3's stricter requirements would ensure better quality at the hardware layer. We also were thinking 3 bandwidth from the computer to the hub would
be nice with all the 2 devices (esp. cameras) feeding it.