HP97 The journey begins

[teenix]

(05-26-2023 09:24 AM)Jonas Sandstedt Wrote:  Tony,

The HP-19C boards looks stunning!
Just out of curiosity, how do you plan to connect the two boards to each other and to the LED display? The original uses the resilient “fingers”, but I guess these are not standard components of today? Should the resilient “fingers” be moved from the broken board to the new replacement boards?

Best regards Jonas

Thankyou.

The boards are still in a prototype stage, so anything can change.

The Battery/Printer board is very similar to the original and (hopefully) will use IDC board to board connectors to the CPU board. The trick is that the top case halve rotates into the bottom case so the pins have to allow for this. The CPU board connects via a ribbon cable which can be inserted into the socket on the key/display board the same as the original.

Unfortunately, the only thing I cannot do is provide a connector to the display, so as you mention, the fingers (which are unobtainable and I have not seen any replacements), will have to be transplanted to the new board. I wouldn't advise soldering a modern socket to the LED display board as the plating on the holes will generally be corroded or blackened and tarnished and it will be difficult for the solder to take. These displays are manufactured similar to the Spice so they too may be damaged by excessive heat, movement or shocks which can dislodge the tiny 7 segment chips from the circuit board and may damage the tiny connecting wires too.

If someone cannot solder, but can unsolder them, they can be sent to me if desired and I will fit them. It will be a bit fiddly, but shouldn't be too hard. I may be able to make up a jig to help out. They can probably be taped inside a Get Well card which should be cheap to mail.

cheers

Tony