Revox G 36, Service Manual

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schematic G-36) provided that the residual RF-signal is at least 35 db below peak
record level (3 % distortion).
A wow- and flutter meter may be required in rare instances only.
3.1.2 De-magnetising
From time to time the ferrous parts in contact with the tape may become magnetised.
When this occurs, especially with head magnetisation, an increase in background
noise will be evident and in serious instances, partial erasure of the tape may come
about. De-magnetisation should be carried out with the appropriate instrument at
frequent intervals and care should be taken at all times to ensure that magnetised tools
do not come in contact with the head assembly. Permanent damage may be caused to
a calibration tape by magnetised sound heads, as they will tend to partially erase the
high frequencies on the tape. They may also have some adverse effects on the overall
performance of the recorder.
3.1.3 Head alignment
Head adjustment should only be necessary when a head requires replacement or
where the setting has been interfered with.
Five adjustment screws are provided I their functions are as follows:
The centre screw no 22 must be undone to remove the head or to adjust the head
around the vertical axis. Adjust screw no 23 at the rear of the head for height, which
will be correct when the upper brass spacer of the heads is divided by the upper tape
edge. Front screw no 23 should then be adjusted to bring the head face vertical with
the tape. Azimuth adjustment must be carried out by turning nut no 24.
Azimuth adjustment of playback head