Upgrading the back plane to 22 bits is easy and
probably would take Tony
Duell only 15 minutes. It will
About 1 minute per connection on average? That sounds right :-)
usually take everyone else a few hours. Wire wrap is
probably the least
difficult to use with a small soldering
iron. You will need to use lead based solder. A total of 16 points
need to be soldered - 4 for each wire
to connect address bits 19, 20, 21 and 22. Leave the insulation on the
wire wrap except where the soldering
takes place. Probably Al Kossow has a manual with a diagram for the
VT103 back plane which show where
address bits 19, 20, 21 and 22 are located.
The only thing to watch for when doing a modification like this is to
make sure that hte pins you're connecting to have not been used for some
other singal (and connected by PCB traces). I don't think this is a
problem with the VT103, but I've never seen one.
-tony