Panasonic PV-D301 Service Manual page 89

If the envelope is output poorly, much noise will appear in the
picture. Then the tracking will lose precision and the playback
picture will be distorted by any slight variation of the tracking
control circuit.
1. Connect the oscilloscope to Pin 30 (Envelope signal) on the TP
Adjustment P.C.B. Use Pin 33 (Head Switch signal) as a trigger.
2. Play back the Alignment Tape (VFMS0004H6C).
3. Confirm that the envelope waveform is as flat as possible (V1/
V(max) 0.7).
If adjustment is required, adjust S Post and/or T Post with "—"
Screwdriver. Refer to
8.3. ELECTRICAL ADJUSTMENT
8.3.1. INITIAL GUIDELINE
The table below shows which adjustments are necessary according to the unit parts and
individual parts to be replaced. Make sure to perform these adjustments shown below as
necessary.
"ENVELOPE OUTPUT
Fig. M7
89
ADJUSTMENT."