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CX-961
7) Adjustment initial value
All automatic adjustments are basically performed
assuming the previous adjustment value as an initial
value so long as the microcomputer power supply is
not turned off (backup is not disconnected) (there are
also several exceptions). If the backup is disconnected
and the GVSW terminal is "L", the automatic
adjustment is performed from the initial vale instead of
the previous adjustment value.
8) Coefficient display of adjustment results
For part of the automatic adjustments (FE or TE offset,
T. BAL, F or T AGC, FE bias and RFAGC), the results can
be displayed and checked in the test mode.
The coefficient display in each automatic adjustment is
as follows:
(1) FE or TE offset
Standard value = 32 (coefficient 32 indicates that no
adjustment was necessary) and the display is
performed in a unit of approximately 46 mV.
Example: For FE offset coefficient = 35,
35 - 32 = 3 3 X 46 mV = 138 mV
The FE offset before adjustment is +138 mV.
(2) T. BAL
Standard value = 32
Coefficient = 33 to 63 ....... TE: Top side - Bottom side <
0
Coefficient = 31 to 0 ....... TE: Top side - Bottom side > 0
Every time the coefficient moves by 1, misalignment
changes by approximately 0.71 to 4.97%.
When the maximum misalignment on the positive side
= coefficient 63, the misalignment is TYP (typical value)
- 45%.
When the maximum misalignment on the negative side
= coefficient 0, the misalignment is TYP (typical value) +
45%.
(3) F or T gain adjustment
Standard value: Focus or tracking = 32, and the display
is performed in a unit of approximately 0.375 dB.
Example: For AGC coefficient = 48,
48 - 32 = 16 16 x 0.375 dB = 6 dB
The adjustment of +6dB (twice) was performed. ("A
half loop gain was used originally, the entire gain was
doubled to obtain a target value".)
12
(4) FE bias
Standard value = 32, and the display is performed in a
unit of approximately 21.5 mV.
Example: For EF bias coefficient = 35,
35 - 32 = 3 3 x 21.5 mV = 64.5 MV
The FE bias alignment before adjustment results in
+64.5 mV.
(5) RF level adjustment (RFAGC)
Standard value = 32
Coefficient = 33 to 63 ....... Direction where an RF level
increases (direction where a gain increases)
Coefficient = 31 to 0 ........ Direction where an RF level
decreases (direction where a gain decreases)
Every time the coefficient moves by 1, the gain changes
by approximately 0.07 to 0.15 dB.
When the maximum gain = coefficient 63, the gain is
TYP (typical value) + 2.69 dB.
When the minimum gain = coefficient 0, the gain is TYP
- 3.93 dB.
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