HP-71B Changing Lower and Upper Halves

[MikeSD]

(03-19-2018 01:43 AM)Dave Frederickson Wrote:  

(03-18-2018 10:22 PM)MikeSD Wrote:  But I have seen a couple versions of the plastic backs. There are at least 2 versions of the zebra strip connector pad arrangements.

Didn't know that. Do you have pics?

I'll see if I have both types and take a pic.

Here's an example

You can probably spot the differences.
* in the top one, there is an unconnected pad, right of center
* in the lower connector, the pad is omitted altogether.
* the fill area to the left of connector is different from top to bottom.
* the number of pads is different between top and bottom. In the connector on bottom, instead of a pad it's just the large area fill.

I've been looking at these to see if I miswired something. Hard to do since everything is straight across. But anything's possible. I've wired two and neither work. That seems odd, so I've been double checking I haven't got an offset.