On Thursday, August 9, 2018 at 10:53:23 AM UTC-4, Jeff Liebermann wrote:
The
political discussion continues until someone mentions Trump, where it
degenerates into one-line comments of little intelligence and less
importance.


Yeah, those Trump Bashers are nothing if not persistent.



Incidentally, I collect old LED HP calculators. You won't see quality
design, materials, and construction like that ever again. After a
rough day of dealing with unrepairable Chinese junk, I rather enjoy
fondling gold plated PC boards, dual shot injected keys that don't rub
off, documentation written in readable English, mostly bug free
firmware, batteries that aren't intentionally overcharged, and wall
warts that don't blow up.


I have a question for you Jeff concerning the HP line.

I have an HP34C that I bought new back around 1980 or so to replace my stolen TI SR-51A. It had always been a little flakey but a quick thump brought it back around. A few years later I decided to have a look inside when it required more physical persuasion to behave. I took a picture of the front keys in case they decided to jump out and get mixed up (they did), but I was surprised to find the half dozen ICs *not* soldered down to the flexible circuit board. They maintain connection by the foam cushion beneath the flex circuit that maintains pressure between the flex circuit and the ICs. I removed each IC, cleaned all the pins and the flex circuit lands, put a tiny bit of dielectric grease on each IC pin, and reassembled. It behaved itself for quite some time. Right now it's been in storage for many years but every once in a while I wonder if the correct solution would be to tack solder them down. I'm sure the foam pad looses a bit of rebound over the years.

What do you do when you run across flakey IC contacts in an HP?