Technical description
HF SSB Transceiver 9323/9360/9390/9780 Technical Service Manual 4-41
Options
Option AM
Option AM allows AM (H3E) users to select and transmit on AM for any channel.
When AM is selected, IC114 pin 9 [1 04-02976 Sheet 1] goes high and controls
two circuits. It switches on V201 [1 04-02976 Sheet 2] and halves the audio
output from the microphone amplifier IC204 pin 7. It reinserts the carrier signal by
switching on IC206/A and V203 [1 04-02972 and 04-03135 Sheet 2]. R284 sets
the level of the reinserted carrier.
The 9390 has AM transmission as standard on the 2182 distress channel.
Option CW
Option CW is used in the 9360 range of transceivers that have the 500 Hz CW
filter fitted. When this option is fitted, the standard SSB filter (Z202) [1
04-03135] is removed and an extra PCB [108-05259] with two filters is added.
The 1814 kHz crystal Z201 is also removed and replaced with a PCB
[108-05260] with three switchable crystal oscillators.
In normal USB/LSB operation, the signal is filtered by Z1, which is 2.5 kHz wide.
When UCW or LCW is selected, the 500 Hz filter Z2 is switched in series with
Z1 by relay K1. K1 is controlled by the software via IC209 pin 7 [104-03135].
The local oscillator switch activates one of three oscillators depending on the
mode selected.
Mode Oscillator
LSB Z1 is on
UCW Z2 is on
LCW Z3 is on
This signal is divided by 2 in IC3/A, then connected to the input of IC206/C
[104-03135].
Option F
Option F consists of an axial fan mounted in a shroud and clamped to the PA
heatsink. The operation of the fan provides additional heat dissipation to the PA
when transmitting continuous data.
After two minutes of transmission, with less than 20 seconds break in between,
the microprocessor IC101 [1 04-02976 Sheet 1] open-circuits the output of
IC114 pin 15. This causes switch V105 to conduct via the pull up resistor R153.
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