|Re: 20b display problem|
Message #5 Posted by Paul Dale on 20 July 2009, 2:31 a.m.,
in response to message #1 by Paul Dale
Fixed the problem.
Examined under magnification, the problem is the end conductor or three on the Zebra strip hadn't seated down properly. The obvious solution is to re-melt it in place.
Then the complication, the unlike other such strips which solder fairly nicely, this zebra strip melts instantly on contact with a soldering iron and by the time I'd figured this out, it had melted past the end of the PCB. Not to worry, a short piece of solid wire can be placed on the pad on the PCB in such a way that it pokes into the zebra strip. Solder the wire to the PCB quickly and the heat imparted to the wire seems to melt the zebra strip in place. In fact, the wire ended up poking through the zebra strip. Be careful here or you'll melt the adjacent conductor on the zebra and the process will have to be repeated. When done and verified, cover the whole thing with a generous blob of epoxy -- I used 90 second Araldite but any should work.
If you're very quick, it is possible to lightly tap the zebra at the bottom most end with the soldering iron and this will melt it onto the pad okay, you do have to be very quick though.
I don't know if this has been mentioned before or not, but the 20b runs fine on one battery.
Now to figure out how to best re-label the keys and attach the debugger pins.