HP-25 Co-luminous segments

[Tom Flatterhand]

I can't find the ROM0 chip. So, I can't find a chip labeled 5061-0430.

Another observation: in the picture of me shining a flashlight from behind on the circuit board where the two chips can be seen. It seems that the 4th contact from the left of the contact strip with the keypad has a direct connection with the 11th contact of the contact strip to the LED display. This is very strange to me since it is this contact of the keypad that connects to the middle row of keys? What is this directly to the display?