Finally I got my HP-67!

[teenix]

(01-09-2020 11:40 AM)Artur - Brasil Wrote:  Hi,

I apreciated very much the replies to my post and I believe all aproaches are good, as they preserve this part of computing history working!

But now I need some information about HP-67. Yesterday I openned my unit again to fix the card reader. Some wires just twisted on terminals, broken soldering and so on. Well, I fixed everything. The card reader is now giving sinals it is alive - not working properly yet.

But another more serious problem arose: the keyboard!
HP-67 can be completely dismantled and give access to all parts of keyboard, which is completely different of HP-11C, 15C, 41C, in which keyboard plate is melted on chassis.

Weel, hp-67 has some rectangular plates for contact, and covering it a very simple sheet of of very simple plastic. Is this correct?
HP-15C has an adhesive plastic, not an usual plastic, covering the plates (disc format), and one thiny sheet of rubber.

After closing my 67, the keys got loose. I tried other solutions, but none worked. Around 4hours trying and nothing.

Just behind HP-67 keys, there is a hole. There should be something between them and contacts?

Many thanks for your support!

Artur

There are locating holes for the key circuit board that mate with the black plastic support. (This is the large part that houses the card reader) These two parts should sit flat against each other. Sometimes they are not lined up properly on reassembly and there can be a larger than normal space between the back of the keys and the key contacts. These two parts are best mated together before placing back in the calculator case.

You will know if the assembly is sitting properly in the case as there will be no movement if you push on any of the corners. If the black plastic rocks when you push, then it is not seated properly.

Also, be careful not to move the board around too much when it is disassembled or you risk breaking one or both of the power wires on the top corner of the circuit board. The other problem that can occur is that one or both of the brass switch connectors can fall out of the back of the switches and float around the circuit board causing shorts. This can damage the circuit.

Yes, just a simple plastic covering. It should also have 2 small holes that mate with small protrusions on the keys retainer.

cheers

Tony