I tried something else... Message #2 Posted by Vieira, Luiz C. (Brazil) on 15 Nov 2009, 5:32 a.m., in response to message #1 by Lincoln R.
... and had some good results.
Hi, Lincoln;
because of both the HP38C and the HP34C, I devoted some time trying to maintain Spices the best way possible. I have some solderless and other soldered units, and all of the solderless have bad contact in the LED display from time to time.
I once reasoned about the three following procedures which significantly reduced bad contact behavior in the IC´s. In fact, I never saw 'Pr Error' anymore since then.
- polish the contacts of the flex circuit - I use metal polisher and a cotton swab;
- apply a thin coat of any micro oil over the contacts - I use a very thin coat of WD40 spread with a clean cotton swab; it does not avoid the IC´s terminals to touch the surface of the flex circuit and also protects the remaining surface of the tracks against oxidation (not highly efficient, just a reasonable protection)
- slightly bent the tip of the IC´s terminals; look at the drawing below.

With these three basic procedures you may achieve so many good results you´ll probably not need to replace the foam. My four solderless Spices work pretty fine, but sometimes one segment or a whole digit misses. I simply tap it gently in my hand sideways and up/downways and it gets back to normal. The LED display contacts are in the edge and I also slightly bent them, one in the opposed direction of the other (as experts do with saw teeth).
Hope this helps.
Success!
Luiz (Brazil)
|