Antitrack_at_networld.at
Date: 2005-08-19 16:52:24
Zitat von "Baltissen, GJPAA (Ruud)" <ruud.baltissen@abp.nl>:
> Hallo Antitrack
>
>
> > Very well, but how would a digital line like this replace a
> > phototransistor like in the original unmodified PC drive?
>
> Because that phototransistor is used in exact the same way: as soon it is
> lit, it pulls a line low that originally was held high to +5V through a
> resistor. The way how it is used makes the circuit digital, not the fact
> that a transistor can behave analogue. Just take 1541 and have a look at the
> write-protect sensor of it.
>
> FYI: although you'll see only two connections, it is still a transistor.
> Normally feeding the Base connection with current will make the transistor
> conduct current. But in this case light is the trigger and therefor the Base
> connection is not needed.
>
> With a bit of luck you can replace the phototransistor with an Hall-element.
Okay. But the Hall-element has 3 lines: GND, 5V, and "Output".
The phototransistor has only 2 connections, and is appearantly just "between"
(?) a +5v line? (I didn't check this!)
Which of these 2 connections that was heretofore reserved for the fototransistor
shall I connect to which of the 3 lines of the Hall-element?
> Just comes to my mind: why do you want to use a magnet again? I am the last
> one to let a magnet near my floppies!
What other options do I have?
Yours
ATT
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