A replacement for the HP-41 zebra connector

[mfleming]

Hi all,

A full write-up on the whole connector replacement project is still in the works but for those who have received their flex order, here are some quick instructions on how to employ them (mind you, it ain't Rocket Science).

Make an initial crease in the flex circuit. Fold the flex over with the contacts on the outside, and then place the holes over the lower posts. Using the fingers of one hand to hold the flex down at the posts, use a fingernail to smooth down the bend in the flex to make a crease. No need to fold it to the finished position just yet.

I've included about twice as much of the medium 2mm O-ring offset material needed for your flex, along with a short length of the hard material to play around with. Cut two pieces of material to a length of about 1.65" to 1.75" (42 or 44mm) so that it will run the length of a row of contacts with a bit extended beyond each end of the contact row.

Place a strip of Scotch brand scrapbooking tape to hold the offset material in place while the flex is folded and the CPU board placed on top. The tape and offsets will be on the back of the flex just above the two rows of contacts at one end of the flex. An alternative to tape would be to use a glue stick and lay down a tacky layer to hold the offset material. Align each offset with the contact pads beneath. Since the cord uses the compression force of the closed case to press the flex contacts against the PCB contacts, you’ll want to line the cord up pretty much with the centerline of the contacts.

Place the flex in the case. I’ve always placed it with the crease towards the bottom and the bottom end of the flex tucked under the protective cover over the keyboard PCB traces. This would be the time to give the flex crease a few more passes with your finger while keeping the cords aligned with the contacts. Since the flex will spring back up when you want to place the CPU board on the posts, I’ll sometimes put a small piece of tape on the upper flex to hold it down over the posts.

Replace the CPU and close the case. Once closed, replace the battery pack. If all is well, you’ll be greeted with the MEMORY LOST message!

~Mark