Male DIN-8 Connector Female 25-pin connector
1 Output Handshake to 5
2 Input Handshake to 4
3 Transmit Data - to 3
4 Ground to 7
5 Receive Data - to 2
6 Transmit Data + Not connected
7 (not connected) Not connected
8 Transmit Data - Not connected
PS: Expand the window to full-screen to view this diagram correctly.
If the cable you have for the Zoomer is the Null Modem cable (i.e. if it's for hooking the Zoomer to a PC), you'll have to switch the input/output connections in this diagram, or wire it as shown above and use a Null Modem adaptor (also available at Radio Shack).
--Steve Henck (ActionVrb2)