<I also have a Trimm- or Sigma- pedestal style 11/73 system with TK50,
<RQDX3/RD53, RX50's. Its a beautiful piece, but I need something much
<more compact, like a desktop BA23ish enclosure or VT103.
BA23 is not much smaller and you will not get all of that in a BA23.
The VT103 is ok, but power will severely limit the system you can build
and there is no preovision for mass storage inside. I forget the Vt103.
Also there is the BA123 {stylish end table} and that has room and power.
You'd need a Terminal for that as the VIDEO console if installed wants
a 19" tube that is huge.
Another compact PDP-11 might be the PRO350 or 380 series.
In the end it depends on what you want the system to do.
Allison