Dave wrote in message
. uk...

"N Cook" wrote in message
...
According to the internet a respected deck in its day.
Had to deal with the slip clutch buried in the mechanism. Photoed before
disassembly just in case. Reassembled and the 2 pinch wheels were
fighting
one another. A strange pair of springs one acting against the other for
the
"reverse" pinch wheel assembly. I must have put one of these springs
back
with wrong anchor position. Correcting that and its playing and FF and
REW
ok.
These units are called 4 head, 4 pairs of screened stereo wires going to
the
head but all seem to relate half the tape. So one question is why 2
pinch
wheels when there seems to be no proper "reverse" side play or loop
control
function as a fixed head.
Repeat sends back to replay the same side.
The "reverse" pinchwheel seems to operate only just clear of the reverse
capstan spindle and has a strange guide that protrudes around the
pinchwheel
and into the recess of the cassette - what is the function of that
protrusion and a non pinching pinch wheel ?
What do the 4 stereo heads do ?

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




I think its an ADF 770. Could it be a 3 head model?

one that can replay the tape while it is being recorded ?



Yes F770 on the front and AD F770 on the back.
Yes 3 head , presumably one erase head and one double head, 2 motors.
why would someone need to replay at record - some semi-pro facility for EQ
checks ?