Commodore VIC-20: VIC-1011A RS232 Interface (Part 1)
Thought I'd have a quick look at this RS232 serial interface for the VIC. It can be used with VICTERM (included on the Penultimate+ cartridge).
The cartridge is labelled "TERMINAL TYPE" ... there was also a VIC-1011B "CURRENT LOOP TYPE" ... from the PCB I'm guessing that maybe they used the same board and just modified the components. It's also interesting to note that the manual states that there's a "limited number of Current Loop cartridges available".
The max. speed appears to be 2400 baud.
VICTERM didn't seem to like VGA output (nothing) but I still had an issue via composite video output as my Japanese VIC-1001 has a different character set ROM (includes katakana).
Manual can be found here:
http://www.zimmers.net/anonftp/pub/cbm/manuals/peripherals/VIC-1011A_RS-232C_Manual.pdf