Technical description
HF SSB Transceiver 9323/9360/9390/9780 Technical Service Manual 4-23
Synthesiser bus
(Shared with synthesiser I
2
C bus.)
The synthesiser bus allows the microprocessor IC101 pins 10 and 11, to
communicate to two synthesisers IC10 and IC13, located on the Rx/Exciter PCB
[1 04-02972 Sheet 1 or IC9 and IC10 1 04-03135 Sheet 1]. These set the
frequencies of VCO1 and VCO2.
PA serial bus
(Shared with the local I
2
C bus.)
The 8–bit output port IC1, which is located on the PA and Filter PCB
[1 04-02973 and 04-03096], reads the serial data and only latches its 8–bit
parallel outputs when a strobe signal is received on pin 7 from the microprocessor
IC101 pin 9. The open collector output controls:
• PA LPFs
• PTT line (within the PA)
• high/low power select
RS232 bus
The RS232 provides serial data communication between the microprocessor
IC101 pins 24 and 25 and external equipment using the RS232 format. The DATA
OUT line is buffered by V103 and associated components. The DATA IN line is
buffered by IC113/F.
Tone generation
The tone generator IC106 has three audio outputs at pins 10, 13 and 17 [1 04-
02976 Sheet 1]. The various tones are generated within the IC by dividing the
common clock input to pins 9, 15 and 18 by factors programmed into the data
input (pins 19 and 20). The tone generator is enabled by a low from the
microprocessor pin 29 applied to IC106 pin 21.
The three audio outputs pins 10, 13 and 17, are filtered by a resistor/capacitor
network and provides the audible signals required for emergency call, selcall and
warning beeps etc.
To Next Page
Loading...
Need help?
General
