HP calculator thermal printheads (HP82143, etc) - test-drb@ccmp.vtda.org

5 May 2000

On May 5, 23:25, Tony Duell wrote:
...
  I have an HP82143 printer (the HP41 dedicated printer)
with a broken
 printhead.

 Today I found an 'HP Digest' with an article about these printers.
 Aparently the conductors on the printhead are aluminium, which explains
 why I couldn't (and still can't) solder to them. And none of the normal
 tricks for soldering aluminium (like : Put a drop of oil on it, scrape
 the oxide layer off under the oil, immediately try to tin it with solder)
 work on this thin film.

 Has anyone here managed to mend a printhead like this? 
No, but could you use silver-loaded conductive paint?  That's what we used
to use to repair the printed tracks on membrane keyboards (including
Sinclair ZX keyboards).  I've used it for a few similar things, and at
least one type can be soldered to, with care, after curing.  I used to buy
it in 3g bottles from R.S., part no 555-156, current stock number
apparently is 186-3593 or 101-5621, costs just over a fiver.

-- 

Pete						Peter Turnbull
						Dept. of Computer Science
						University of York