I bought a new Ferguson FTV210N 21" television and it
seems the picture is too big vertically I eventually found a
'pot' (potentiometer) which seems to control the picture hight
but even at maximum adjust the picture is still too (big slightly).
(There didn't seem to a similar pot to do the same thing
horizontally, incidently, is this normal?)

Any ideas as to what is the problem???

I mean surely adding a bit more resistance would fix it??

Initially I though the problem might be 'fixable' in the TV's
service mode (is it indeed has one) but the pot controls it.