Help ID this PowerBook modem card

Could be a PB 100 modem.

its definelty not for the 500 series... i´ve got like 10 of them (the 500 ones )

lol jsut saw the date... *headdesk*

Looks identical to Powerbook 100/140/145/160/170/180 Domestic Modem, Internal, Apple P/N 661-1621 as pictured in my Apple Module Identification Service Guide, Sept 90 edition (also shows marking 820-4021- B) .

k, thanks. So definitely not a Duo modem then.

The Duo one is half that size, sort of square, see picture at

http://www.haun-online.de/Macintosh/HTML/duo230.html

My Service Guide mentions two flavors: a domestic version with RJ-11 connector, and an international version with a Mini DIN-8 connector. Perhaps someone with more familiarity can jump in and comment on external adaptors or whatever that connect to that DIN-8 version...