Chapter 6 335
General Troubleshooting
Block Diagram Description
Figure 6-7 Phase Lock Loops
Fractional N PLL (part of A14)
The fractional N PLL produces an output of 60 MHz to 96 MHz. This
PLL output serves as the reference frequency for the YTO PLL. A
one-to-one relationship in frequency tracking exists between the
fractional N PLL and the YTO. A change of 1 MHz in the fractional N
PLL will produce a 1 MHz change in the YTO frequency.
IF Section
The IF section processes the 10.7 MHz output of the RF section and
sends the detected video to the ADC/interface section. The following
major assemblies are included in this section:
• A3 interface assembly
• A4 log amplifier/cal oscillator assembly
• A5 IF assembly