Gday Lewis
As Peter noted, RJ and Din are merely connector specs
and rs232 is a comms type. No matter what way you go,
if you need rs232 at the scope end, that defines everything.
If you just want to make a simple cable without big lumps or joins,
you can always get a raw converter unit like
http://www.aliexpress.com/store/prod...643595233.html
and wire it up with a cable and connector to suit.
Only three wires are reqd for comms.
That, or you can go wireless
The latest Silicon chip magazine has a great article on a wifi system with built in webserver and TCPIP stack. The boards are the size of yr fingertip and ( supposedly ) only cost about $5.
Ive only just started reading the article, but it looks like they would still need a max chip at each end as they run at 3.3V.
Andrew