Standard Horizon Quest-X GX1500S, Руководство по обслуживанию

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9
VCO output passes through buffer amplifier Q1024
( 2SC5006 ) to obtain stable output.
1050 Hz Weather Alert Decoder
1050 Hz Weather Alert signal from the FM IF subsystem
IC
Q1039 ( TA31136FN ) is demodulated by Q1049
( 2SC4154E ) then is applied to 16-bit MPU IC Q2003
( M30624FGPGP ) on the CNTL Unit.
Circuit Description
MPU
Operation is controlled by 16-bit MPU IC Q2003
( M30624FGPGP ). The system clock uses a 14.74560 MHz
crystal for a time base. IC Q2002 ( PST597CN ) resets the
MPU when the power is on, and monitors the voltage of
the regulated 5V power supply line.
EEPROM
The EE-PROM Q2004 ( AT24C128N ) retains TX and RX
data for all memory channels, prescaler dividing, IF fre-
quency, local oscillator injection side, and reference oscil-
lator data.