LA75695VA

No.7637-8/13

V14. C/S beat [IC-S]

(1) Apply DC voltage to the external AGC IF AGC (pin 17) and adjust the voltage.

(2) fp = 45.75MHz CW; 10mVrms

fc = 42.17MHz CW; 10mVrms – 10dB

fs = 41.25MHz CW; 10mVrms – 10dB

(3) Adjust the IF AGC (pin 17) voltage so that the output DC level at test point A becomes 2.4V.

(4) Measure the difference between the levels for 3.58MHz and 0.92MHz components at test point A.

V15. Frequency characteristics [fc]

(1) Apply DC voltage to the external AGC IF AGC (pin 17) and adjust the voltage.

(2) SG1 : 45.75MHz continuous wave 10mVrms

SG2 : 45.65MHz to 39.75MHz continuous wave 2mVrms

Add the SG1 and SG2 signals using a T pat and adjust each SG signal level so that the above-mentioned levels are

reached and input the added signals to the VIF IN.

(3) First set the SG2 frequency to 45.65MHz, and then adjust the IF AGC voltage (V17) so that the output level at

test point A becomes 0.5Vp-p. ····· V1

(4) Set the SG2 frequency to 39.75MHz and measure the output level. ····· V2

(5) Calculate as follows :

fc = 20log

(dB)

V16.V17. Differential gain, differential phase [DG, DP]

(1) Internal AGC

(2) fp = 45.75MHz APL50% 87.5% modulation video signal Vi = 10mVrms

(3) Measure the DG and DP at test point A.

V18. No-signal AFT voltage [V13]

(1) Internal AGC

(2) Measure the DC voltage at the AFT output (B).

V2

V1