Don't know for sure but on many Sony models of that age you have to...
(1) Select the Channel Position.
(2) Press Arrow Up (shift) + Diamond Symbol, together on the remote control, to enter UHF Tuning.
(3) Then use - / + to tune.
(4) Same as (2) to store & exit UHF tuning.
Cobweb
November 2005
I can answer this question...
HOW CAN I TUNE IN MY 20INCH SONY TRINITRON MODEL KV-M2 151U?