EQ6 polarscope LED windup and short

[sculptor]

My EQ6 failed on power-up, with the main red "power-on" LED flashing fast. Gasp! First thought was electronics full of water (after observing with 1/4 inch of ice on the car the night before). Opened up electronics case. Dry as a bone. Next thought: I'd been a bit generous with the lithium grease on the polar axis latitude adjustment, and perhaps the orange-oil solvent had done for something. Looked to see if the grease could somehow get into the electronics via the rear polarscope hole. Saw the polarscope LED leads. Aha! Perhaps insulation dissolved? Gave a gentle prod. Wires snapped off! Disconnected 2-pin plug for LED from main board. Fault gone. Sadly, no chance to repeat as wires physically munged at this stage. But realized failure mechanism: When I put the counterweights on (only need 25 Kg your honour), I have the declination axis pointing sky-ward. Same for transporting. If I don't always rotate the shaft the same way, the LED cable could have gotten wound up tighter and tighter by one revolution each session, until eventually snappo, short circuit, failure. Anyway, easily fixed. A as I use a precision compass and level rather than polarscope, I just threw the LED away.

Any others seen something like this?

[Astroman (Andrew Wall)]

Never heard of that happening before. I have turned my Dec axis quite a few times and the polar scope still works. Was the polar LED added on after manufacture or during?

[sculptor]

The polarscope LED was original equipment. But it is rotating the polar axis, not the declination axis, that causes the cable to wind up. On closer look, it appears that the LED is on a sort of slip-ring, and perhaps it jammed. Guess the point of my story is, if the mount does fail, at least have a peek at the polarscope LED cable.

Cheers,
Mike