Re: 1541II and 1571 repair (fwd)

From: Ojala Pasi 'Albert' (albert_at_cs.tut.fi)
Date: 1999-03-16 12:21:49

>    1571 disk drive, when the drive powered up red led 
> stay on and motor run continuously and green led stay
> off.
> 
>    1541 II disk drive, when the drive powered up red 
> led stay off and green led stay off and motor run 
> continuously.

It could be one of the TTL chips in the reset circuit
UD3 (74LS86) or maybe UA1 (74LS14) or UB1 (74LS06).
Measure the reset signal to see if it goes high after powerup.
If it doesn't, it's probably one of these chips.

I repaired two drives this way a couple of years back.

-Pasi
-- 
"Lyta Alexander. She was the first commercial telepath assigned to
 Babylon 5 little over two years ago. She arrived January 3, 2257.
 She left about six weeks later."
	-- Garibaldi to Sheridan in Babylon 5:"Divided Loyalties"
-
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