It is a very basic 300 BAUD modem built into the case and wired up to
unused pins on the RS232 connector where a custom phone line adapter
plug would be used.
The MN74HC943N is a 300 BAUD modem chip
https://www.digchip.com/datasheets/parts/datasheet/321/MM74HC943N.php
The NM80C98N is a 3 state hex inverter
Darren Clark
On 1/10/24 20:05, David Plass wrote:
Hi all,
I just bought an NEC 8201 and it has a strange mod inside: there's a
daughterboard on top of the motherboard with 5 or 6 alligator clips
attached to various spots on the board including 3 or 4 on the RS-232
connector.
For more details, I published a video to see what I'm talking about:
https://www.youtube.com/watch?v=Q7G7Ozaf_mk
Does anyone know what this is?
-David
