A radio amateur in Nottingham,Vic G0RVA, recently bought one of these Belcom rigs. It appears to be an all-mode 70cm rig, although I am not familiar with this unit.
I know Belcom did a 2m version (the famous Liner-2, which I did once own) and a similar version for 70cm. The Liner-2 was a modification of their 10m version, which I don’t think was ever sold in the UK. Inside Vic’s rig was what looked like a canned preamp with the marking “AngleLinear” but again I am not familiar with this unit. Angle Linear appear to be based in the USA http://anglelinear.com/ .
In its day, the 2m Liner-2 transformed 2m. It was a synthesised SSB rig and was frequently pushed too hard so that splatter was a problem. I was amazed how far I could work on 2m SSB with 10W pep. From Cambridge I could work stations that would have been impossible on FM or AM. I found I could work 200-300km with a simple antenna under ANY conditions.
Many were critical of these early Belcom transceivers, but I enjoyed my Liner-2 as did many others. Later I bought an ICOM IC202 which was a better radio, but with less ERP. The IC202 had a mock military style, that really was not too clever.
The “coming of age” of 2m SSB marked the change from “tuning high to low” to single frequency working. Sadly, there is far less activity on 2m SSB outside of contests so people think VHF is only really any good for local QSOs. With 10W SSB, or even less, it is possible to work a long way on VHF irrespective of conditions. From my current QTH, I think 200km is reachable with 5W pep and a 3 el beam on 2m. It is not that different on 70cm where I use 5W pep and a 5 el beam. Both my beams are hand rotated.