Capable of 1w or a bit more with tweaking. Free running VCO at 23cm but synthesizers were available, the original multi-channel using a CB radio sysnth chip and the other Worthing offering was based on a Plessey SP5055 and gave a single channel from a xtal multiplied by 256.
Originally offered as a kit by G8CMQ (?) in the 80s, it was taken on by the Worthing ATV Repeater group so it's also known as a 'Worthing'
Your PCB may be home made as most I saw were tinned, not bare copper
Looks like someone as added a PA. The usual method was to add a Mitsubishi M57762 brick and that could give 18 to 20w out.
If it has a M57762 its worth hanging on to as it can produce 4w of DATV with shoulders more than -40 dBc.
The small box may be a preamp for 23cm but I don't recognise it.
Clive G3GJA / G8EQZ
With schematic now downloaded
Feel more confident about applying a power supply.
Sorry for delay in responding.
Away on holidays, recently.
73 Mike G4GUG.