MITSUBISHI ICs (TV)
M52769FP
PLL-SPLIT VIF/SIF
15. SIF detection threshold level TSIF
SG21 is applied to SIF IN and the input amplitude is swept.
Then, the level of SG21, TSIF, is measured at the time when the
DC voltage of SIF CARRIER DET OUT (TP16) has just begun to vary.
16. RF AGC voltage V3F
SG21 is applied to SIF IN and the input amplitude is swept.
Then, the level of SG21, V3F, is measured at the time when the
DC voltage of RF AGC OUT (TP3) has just reached 1/2Vcc.
17. AF S/ N (S/N F)
1. SG19 is applied to SIF IN and the output noise of AUDIO OUT (TP12)
is measured. The measured noise is named VNF.
2. S/N F is,
VoF [mVr.m.s]
[dB]
S/N F = 20log
VNF [mVr.m.s]
MITSUBISHI
ELECTRIC
14