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My astronomy project:
1, AstroEQ for EQ6 mount ?
On older versions of SkyWatchers EQ6 mounts there is a bug in the driver of the stepper motors. It cause the RA follow stars with wrong speed. In the original hand terminal there is a compensation for this. When controlling the mount from a computer I use EQMOD which has a RA drift compensation for this. But it cause problem when trying to do something with the mount as I have done. In these older mounts the driver can't be flashed to a newer version. Maybe the easiest way is to replace the driver in the mount. AstroEQ can maybe be used to replace the EQ6 hardware stepper motor driver.
RA drift problem:
This is how it looks like when not using the original control. RA, the blue graph, drift away slowly. In EQMOD there is possible to set the Drift compensation to cancel this effect. If the EQ6 driver board has this bug the sidereal speed will not be correct. Above can be seen how the auto guider try to slow down the RA speed. It's the guide pulses we see at the arrow. It got worse after my belt modification because I didn't keep the original gear ratio.
Normally we had seen a periodic error curve here. But now when the RA sidereal speed is wrong the RA, blue line drift away. The RA drift compensation was not enough. I have set the RA drift compensation to = -6.
If this problem with the drift compensation is too big I can always replace the driver board with something else. I have this AstroEQ driver which is EQMOD compatible.
It's very compact and I think it will fit inside the EQ6 cabinet, but have to think about it.