Conversion to 9825T
I got two board from Paul Berger on the vinthp mailing list which would convert the 9825A to an 9825T:
- The A24 (09825-66524) Ebenezer board containing RAM and a ROM set
- The A25 (09825-66525) SKOAL board
To update the machine first remove the System ROM pack from the 9825A, then cut a few traces on the CPU board:
Installation pictures from CuriousMarc’s video
Ebenezer board (1st above the tape drive board)
followed by the Skoal board. I lacked the nice HP spacers for that so I used some nylon spacers and screwed them in: