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The test has been designed for high quality
pickups, and many pickups on the market
today will not be able to track the first band,
even at their maximum tracking force. These
pickups are typically those with minimum
tracking forces above 11/ 2 grams. In testing
such a pickup, the tracking force should be
set at its maximum recommended force. If a
large, unstable display is observed on Band 1
(aside from the warp effect), add a weight
and, if any change is detected, the pickup is
mistracking the first band. It is useless to con-
tinue with the test since the mistracking point
is less than 15 cm/sec at 10.8 kHz. The cus-
tomer should be advised to operate the
pickup at the maximum force to minimize the
damage to his records due to excessive mis-
tracking.
Once tracking on the first band has been
established, proceed through Bands 2,3, and
4 or until mistracking occurs as shown in
Figure 21.
Note: Once mistracking is observed, do not
continue to play the band, as severe
record damage will result.
Repeat the test on Side 2. The skating com-
pensation is optimum at the desired tracking
force when mistracking occurs at the same
Fig. 21
band number for each channel. The desired
tracking force chosen should be the minimum
tracking force at which the pickup will track
19 cm/sec on the high frequency test, 25 cm/
sec on the mid-frequency test and 15 cmlsec
on the low frequency test. Although some
retesting may be necessary to find the opti-
mum force, the optimum skating compensa-
tion should be set using the high frequency
test and not changed for the mid- and low-
frequency tests.
In all cases, the observation of mistracking is
enhanced if the operator listens to the signal
while watching the oscilloscope display. Mis-
tracking sounds like a mid-frequency "buzz"
while proper tracking sounds like a high fre-
quency "whistle."
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