Netronics Phoneme generator info

[Jules Richardson]

Random find in my local book store's pile of scrap electronics heading for 
recycling - a Netronics Phoneme speech synthesizer. IC dates all around 
mid-1982.

I just have the board, no case or anything, but it appears to be reasonably 
self-contained: there's a connector for PSU, a phono which I'm guessing is 
speaker out, pots for volume and pitch, and a DB-25 connector. The DB-25 
only has pins 1,2,3,7 & 20 in the socket, so I'm assuming it's  RS-232.

Does anyone know anything about these? Assuming it still works (it looks 
like it just expects 6-9VAC or thereabouts on the PSU connector), is the 
control protocol documented anywhere? DIP switch settings? (there are 8 on 
the board, labelled BSY, 3, 2, /C, /C, B, P, C)

Looking at the PCB traces, it appears to allow data input by either pin 2 
or 3 (dictated by the '2' and '3' DIP switch settings), but there's no data 
sent out down the serial line, so communication is write-only.

I suppose it's possible that I hook up a terminal and (assuming that I have 
the line parameters right) start typing English, but it's probably not that 
simple ;)

cheers

Jules