Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!ucsd!sdcc6!dino!dlou
From: dlou@dino.ucsd.edu (Dennis Lou)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: Making a floppy drive ignore high density hole
Keywords: 3.5 drive, HD, DD, switch
Message-ID: <11962@sdcc6.ucsd.edu>
Date: 21 Jul 90 08:52:34 GMT
References: <803@digi.lonestar.org> <1990Jul19.193954.29829@cunixf.cc.columbia.edu> <25160@nigel.udel.EDU>
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In article <25160@nigel.udel.EDU> ih@udel.edu (Charlie Ih) writes:
>In article <1990Jul19.193954.29829@cunixf.cc.columbia.edu> ezk@cunixe.cc.columbia.edu (Erez "HWank1" Zadok) writes:
>>In article <803@digi.lonestar.org> mfrohman@digi.lonestar.org (Matthew Frohman) writes:
>.....
>>:-) utilize my 5 years of EE studies and put a switch instead.  I opened my
>>machine and after a few screws (no jokes please) got to the circuit board of
>>my 3.5 drive (I think it is a Mitsubishi) where I found a small switch on
>>the front right corner of the board.  I soldered out that switch.  Put a
>>hole in the left front panel of my drive and made sure the location of the
>>external switch did not interfere with anything inside. .....

>The information is very helpful to others as well.  I hope we can have
>more of this kind information to help each other.  Congratulations
>and thanks.  Just curious, why could you just leave the switch there
>(in open position) and connect the "external" switch in parallel with it?
>This would require less work but more important have less chance to damage
>the circuit board.  Since I don't know the actual situation, maybe
>the removal of the switch was necessary.  Thanks again!

On my Sony, DD closes the switch while HD opens it.  It makes sense
because the switch isn't activated on HD since HD has a hole.  With
DD, the blocked hole touches the switch.  I plan on cutting the trace
on my switch, then putting a 3 position on it giving me "Forced
1.44M", "Forced 720k", and "Autodetect" modes.


You can probably imagine the circuit yourself...


--
Dennis Lou                Disclaimer: I don't use lame disks.
dlou@dino.ucsd.edu         "But Yossarian, what if everyone thought that way?"
[backbone]!ucsd!dino!dlou  "Then I'd be crazy to think any other way!"