The Museum of HP Calculators
HP Forum Archive 14
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Message #1 Posted by Robert on 12 Aug 2004, 1:21 p.m.
Today I bought a Hewlett-Packard 9825A from 1976, in a second hand shoop for $3. With all manuals.They didīt know what it was. So I am happy. Robert from Sweden
Message #2 Posted by David Ramsey on 12 Aug 2004, 6:51 p.m.,
in response to message #1 by Robert
Damn. That's even better than my $30 tape drive with three tapes!
Have fun! The tape drive often needs work on the old 9825s, but it's not hard to do.
Message #3 Posted by marais on 13 Aug 2004, 5:01 p.m.,
in response to message #2 by David Ramsey
I just paid 325 for my 9125, and the tape drive needs to be redone. Any hint appreciated!
Message #4 Posted by David Ramsey on 15 Aug 2004, 1:09 a.m.,
in response to message #3 by marais
Well, I've never actually heard of a "9125", but the problems tape drives on the desktop HP calcs have are pretty much the same as the problems the handhelds have: dirty heads and disintegrating rubber on the drive wheels.
The larger size of the desktop machines makes them easier to work on.
I replaced the rubber on the drive wheel of my 9825 with heat-shrink tubing. It's true! Slide large tube over the cleaned drive wheel, heat shrink, trim with razor blade.
Cleaning the tape head can be done with Q-tips and alcohol.
Message #5 Posted by Vassilis Prevelakis on 15 Aug 2004, 5:30 p.m.,
in response to message #4 by David Ramsey
I generally avoid heat shrink tubing because unless you glue the tubing to the metal base, it will eventually come off.
After doing any repair to the spindle I usually use a sacrificial tape to wind to EOT and then rewind to BOT a couple of times to make sure that the repair can take the heat loads and strain.
Check also the "fix your gummy wheel" section at the end of a previous posting:
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