The easy-to-operate PM 6307 — Wow and Flutter Meter — is
designed to identify and quantify unwanted speed variations
in audio and video tape recorders, record players and movie
projectors. With its X-tal controlled oscillator giving the
choice of 3.00 kHz or 3.15 kHz (DIN standard) it is possible
to make very accurate wow and flutter checks and alignments.
Readout of speed variations of, for example, a recorder is
indicated on two separate analog meters, one for drift and
one for wow and flutter. Calibration of the drift indicator
is simple, being achieved by depressing the ZERO button,
while the SET ZERO control is adjusted for zero indication.
The use of the X-tal oscillator eliminates the long warm-up
time associated with normal R — C types with the advantage
that the instrument can be used immediately after switch-on.
The measuring ranges for drift and flutter are separately
selectable by pushbuttons.
There is also a convenient choice of three positions for wow
and flutter measurements. With the filter switched ON, the
frequency response is "weighted", according to DIN Standard
In the filter OFF position, a linear frequency response of
0.5 Hz to > 500 Hz is available and the "unweighted" flutter
For special measurements beyond the normal everyday usage,
there is a connector on the rear panel to apply a desired