ALBA T717

On BBC, sound is only just audible with the
controls at maximum. A certain amount of hum
also is present on the sound. ITA sound, although
considerably better than BBC, is definitely below
normal.
This set has also developed a video fault which
requires the contrast control to be set at maximum
at all times to receive a satisfactory picture. I suspect these faults originate in the turret
tuner.-M. J. Lovell (Southend-on-Sea, Essex).
The cause of the faults described could be in
the tuner, but equally, misalignment of the sound
and vision i.f. channels could be responsible. The hum on sound is probably due to vision signal breakthrough into the sound channel, and this is
invariably caused by misalignment of the sound
i.f. channel.
If the trimmers have been altered recently, then
suspect misalignment. Also check the aerial
system and, if necessary, the tuner valves for
emission.