RK05 alignment - without alignment pack?

Philipp Hachtmann hachti at hachti.de
Sun Dec 13 18:07:36 CST 2009


Hi Tony,

>> How does the positioner find track 0?!?
> 
> It's all done with that optical transduce (the glass scale, the lamp, and 
> a couple (or is it 3) photodetectors under the carriage). IIRC it moves 
> the heads towards the spindle, then as soon as it gets a valid signal 
> from that transducer, it locks to it and calls it cylinder 0.

>> Does it use the end of range microswitch and then count? This is a bit 
>> unclear to me.
> 
> AFAIK the microswitch is only used to disconnect the emergency-retract 
> battery when the heads are fully retracted. It's not part of the 
> positioner system, it wouldn't be repeatable enough.

Six sensors....!
As far as I understand the documentation, the "outer limit" switch *IS* crucial...! Huh... :-(

> Did the drive work properly after re-fitting that glass scale? 
No *g*
But I don't know if this was the problem. Better: if this was ONE of the problemS. But I assume that 
I'll run in trouble with the sensors..



>> everything is moving a bit. Last but not least, a PSU regulator failed 
>> with great optical effects. 
> 
> Which one? I am wondering if you have failed power transsitors on the 
> servo amplifier board that are overloading one of the power rails. Ma be 
> worth checking.
20V I *think*. I did not have the impression of overload. This happened after about one hour of 
operation. After many years... Gave some nice sparks.


-- Philipp


-- 
http://www.hachti.de



More information about the cctech mailing list