My STXL-6303E with guiding filter wheel suddenly will not download data when cooling, or even after cooling. Camera and filter wheel operate normally so long as I don't turn cooling on. When cooling goes to 100%, MaxIm DL hangs completely except for a "Camera Error (8)" popup, which means Timeout--consistent with what I see. I have to restart the camera and MaxIm after this. This hanging and error happens even after I've turned cooling Off. In other words, once cooling goes on, the camera then fails on its first attempt to send an image back to the PC. The cooling itself gets to 100% and then -35C as rapidly as ever, and images do improve with low temp (in TheSkyX)--so there's no obvious power supply or cooler failure. When operated directly from TheSkyX 10.5.0 with cooler on, the download also occasionally hangs and TheSkyX locks up. Drivers and Firmware are current per DriverChecker64. ASCOM is current at 6.2SP1. Win 10 Pro is up to date, and restarting PC makes no difference. My program is dead until I can get relief on this. Thanks.
Follow-up 36 hours later: I just ran > 100 images without a problem while during max cooling (100%) and under normal cooler control (50% power). Cooling and imaging behavior seemed completely normal. But something catastrophic happened Saturday night. Switched if I know what. (Of course it had to happen at the beginning of a severe-clear, windless, new-moon night.) I am confident that the AC power supply was OK Saturday night (no complaints from other owners of the building's 20 telescopes), so the only difference I can imagine between now and the night with problems is the ambient temperature, now 15C higher than the other night. That speaks to something physical. So I guess I'll drive up to the mesa to clean and replug all the power and USB connections, check the camera fan, update Win 10 etc etc. Will report back after tonight's attempted runs.
That's a good idea. It's really hard to explain your symptoms except possibly as a poor connection somewhere. If the power supply wasn't supplying enough current, the voltage would drop and then the cooler would turn itself off to protect the camera. But that's not what you are seeing. Error 8 is a problem with the USB connection. If you are using a USB hub, they are often problematic. Most do not like cold conditions, since they use cheap ceramic oscillators instead of crystals and go off-frequency. Also many can't handle the traffic if you run a camera and autoguider through the same unit.
Followup: Successful observing again last night, several hundred images without camera incident. On yesterday's trip up to the mesa, I made several improvements: Cleaned pins on camera USB and power connections: easy enough. Strain relief: Tied camera cords to camera at strategic points, to relieve all strain on plugs at the camera. Installed strategic right-angle USB adapter at PC (in tight quarters inside its temp-controlled chamber). Normally I would minimize connection count, but this one renders much more good than harm. Ferrites: In case there's new electromagnetic noise somewhere in the hosted facility, I installed ferrites at each end of USB and power lines to the camera and on a few other low-voltage cables. As I learned in lightning-prone Kansas: ferrites are your scope's best friend. A ferrite at each end stops most common-mode noise. I keep sizes 3 mm (small wires), 5 mm (most USB cables), 6 mm (most ethernet cables), and 9 mm (power cords) handy. It may be only limited protection, but it's really cheap and zero-maintenance. One of these remedies worked. I'll probably never know which. And I would never ever put a USB hub, no matter how high in quality, between my PC and camera. I could never recommend anyone ever do so under any circumstances. It simply ends in tears. In any case, there was probably never anything really wrong with the camera or PC, and the connectivity issue seems OK now, so let's consider this thread Resolved. Thanks.
