I'd not appreciated before, why VCR mode change motor and gearboxes always
have a small drive band from the motor pulley.
These Arcam gearboxes are cogs right through. Alright at the outset but any
dirt, wear etc that increases the back torque then there comes a time when
the motor cannot start to spin because there is no give in the gear train.

Final repair attempt, the (slightly cut -down to let in band) casing and
spindle from a small
motor, with magnets removed, to replace the original. Then a rubber drive
band around the rotor, to the motor, repositioned wherever is suitable.
Should provide that bit of start-up give and also an extra 5:1 mechanical
advantage.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

Thats probably the secret for these Arcam /Alps switch banks.
With an added rubber drive band stage it now works
reliably. If too much added gear ratio then it will
time-out going from extreme positions 1 to 6 or 6 to 1, though.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/