JVC HR-D540EE - Page 26

Cn
Height 1) Run tape and observe the control head area.
See Figs. 1-5-9 and 1-5-11. | 2) Turn screws @), @ and @) by small and
(Symptom: !ow audio and equal amounts until 0.1 to 0.2 mm of the
control signal levels) head core bottom can be seen.
Note: If difficult to observe, play stairstep signal
<<! A=0.1-0.2mm of MH-2 Alignment Tape and adjust for
maximum audio output and control pulse
level,
Tape A/C head
Head core FM linearity Refer to upper drum assembly items.
Fig. 1-5-11 If adjustment is major, again check the azimuth.
Height Adj
Control head phase 1) Play stairstep signal of MH-2 Alignment
See Fig. 1-5-12 Tape and observe the FM waveform. Set for
PB FM: Main board TP206 Tracking Preset by pressing the + and —
DRUM FF: Main board TP411 buttons simultaneously in the onscreen
mode.
Screw @) 2) Loosen screws (4) and(@). Set the A/C head
positioning tool on screw ®, with the stud
AIC head inserted into the nearby oblong hole.
3) Turn the tool first to position the A/C head
fully toward the capstan. Then gradually
(From Drum) return it toward the drum and stop at the
Screw ©) position of maximum FM waveform output
level as shown in Fig. 1-5-13.
Fig. 1-5-12 CTL head phase | 4) Tighten screw (©) . Remove the tool and
,
it
tighten
screw
@.
F
MH-2
(49
um
head)
-—
adjusting
point
(To Capstan)
(Wide head) Bre
FM output level
oe
~ (narrorw head)
CAPSTAN
CTL HEAD position
Fig. 1-5-13 CTL head phase
Note: Trigger the oscilloscope externally signal from TP411
(DRUM FF). Use (+) trigger for MH-2 alignment tape.
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