Rec Color (Colour) Level; Video Eq (Frequency Response) - JVC SR-VS30E/EK Service Manual

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(7) Record the signal (A2) in the mode (B2), and play back
the recorded signal.
(8) Set the VCR to the manual tracking mode.
(9) Repeat steps (1) to (5) in the mode (B2).
(10)Record the signal (A2) in the mode (B3), and play back
the recorded signal.
(11)Set the VCR to the manual tracking mode.
(12)Repeat steps (1) to (5) in the mode (B3).
H. rate
Fig. 3-3-2a

3.3.3 REC color (colour) level

Signal
(A1)
Alignment tape(S-VHS, SP/LP, Color(colour)
bar) [MH-2H]
(A2)
Ext. input
(A3)
Color (colour) bar signal [PAL]
Mode
(B1)
S-VHS SP
(B2)
S-VHS LP
Equipment
(C)
Oscilloscope
Measuring point (D1)
TP106 (PB. FM)
(D2)
PB color (colour) output of the LPF
External trigger
(E)
TP111 (D.FF)
EVR mode
(F1)
Jig code "57"
EVR address
(F2)
A : 02
(F3)
Jig code "20" and "22"
(F4)
Jig code "18" or "19" (Channel +/-)
Specified value
(G)
SP: "B" x 125 ± 5%
LP: "B" x 125 ± 5%
Adjustment tool
(H1)
Jig RCU [PTU94023B]
(H2)
• LPF [PTU93006]
39 µH
1 kØ
PB. FM
120 pF
Fig. 3-3-3a LPF
(1) Connect the adjustment tool (H2) to the measuring point (D1).
(2) Apply the external trigger signal to D.FF (E) to observe the
PB color (colour) waveform at the measuring point (D2).
(3) Play back the signal (A3) in the mode (B1) of the align-
ment tape (A1).
(4) Set the VCR to the manual tracking mode.
(5) Adjust tracking so that the PB color (colour) waveform
becomes maximum. Make a note of the higher PB color
(colour) level as "B" at this time.
(6) Record the signal (A3) in the mode (B1), and play back
the recorded signal.
(7) Set the VCR to the EVR mode by transmitting the code
(F1) from the Jig RCU.
(8) Set the EVR address to (F2) by transmitting the code (F3)
from the Jig RCU.
(9) Transmit the code (F4) from the Jig RCU to adjust so that
the higher level channel becomes the specified value (G)
of the note "B" level as shown in Fig. 3-3-3b. (Adjust be-
fore recording, then confirm it by playing back.)
(10) After adjustment, record the signal (A3) then playing it
back again. At this time, confirm that there is no invert-
ing phenomenon or noise appearing on the playback
screen.
3-3
Y level
EE/PB Y level
(See Fig. 3-3-3a.)
180 µH
629 [kHz]
PB COLOR
(PB COLOUR)
180 pF
(11) Release the EVR mode of the VCR by transmitting the
code (F1) from the Jig RCU again. (When the EVR mode
is released, the adjusted data is memorized.)
(12) Repeat steps (3) to (11) in the mode (B2).
Note:
• After adjusting, always perform the confirmation and
re-adjustment of the item 3.4.1.
V. rate
Fig. 3-3-3b REC color (colour) level

3.3.4 Video EQ (Frequency response)

Signal
(A1)
Ext. S-input
(A2)
Video sweep signal
Mode
(B1)
S-VHS SP
(B2)
S-VHS LP
(B3)
Picture Control / Smart Picture
REC : Normal / Natural
PB
Equipment
(C)
Oscilloscope
Measuring point (D1)
Y OUT terminal (75Ø terminated)
Frequency marker(D2)
3 [MHz]
External trigger
(E)
TP111 (D.FF)
EVR mode
(F1)
Jig code "57"
EVR address
(F2)
A : 03
(F3)
Jig code "20" and "23"
(F4)
Jig code "18" or "19" (Channel +/-)
Specified value
(G)
SP: 3.6 ± 0.4 div. (–1 ± 1 dB)
LP: 3.2 ± 0.4 div. (–2 ± 1 dB)
Adjustment tool
(H)
Jig RCU [PTU94023B]
(1) Apply the external trigger signal to D.FF (E) to observe
the Y OUT waveform at the measuring point (D1).
(2) Record the signal (A2) in the mode (B1), and play back
the recorded signal.
(3) Set the VCR to the manual tracking mode.
(4) Set the VCR to the EVR mode by transmitting the code
(F1) from the Jig RCU.
(5) Set the EVR address to (F2) by transmitting the code (F3)
from the Jig RCU.
(6) Set the slope of the oscilloscope to the channel having
higher (D2) marker level of the Y OUT waveform [signal
(A2)]. Then set the 100 kHz marker level to the "4" scale
on the oscilloscope. In this condition, transmit the code
(F4) from the Jig RCU to adjust so that the (D2) marker
level reaches the specified value (G).
(7) Release the EVR mode of the VCR by transmitting the
code (F1) from the Jig RCU again. (When the EVR mode
is released, the adjusted data is memorized.)
(8) Repeat steps (2) to (7) in the mode (B2).
100 kHz
Scale 4
Four scale
(4 div.)
Specified
value (G)
Fig. 3-3-4a
Video EQ (Frequency Response)
Specified
value (G)
: Edit / Distinct
1 MHz 2 MHz
Frequency
marker (D2)
5 MHz
V. rate

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