Adjustments
7-24 HF SSB Transceiver 9323/9360/9390/9780 Technical Service Manual
q Switch off the transceiver and disconnect the DC supply and resolder fuse
PA O/P.
If the fuse is broken, replace it with two strands (2 × 0.2 mm TCW) taken
from a piece of 7 × 0.2 mm cable. Solder the wire to the two stakes. Extend
the centre of the wire up to form an inverted Vee. Only solder at the wire
ends attached to the stakes.
Output power
For PA assembly 08-04963 (2 to 26.5 MHz), link X1 is located above P1. You
must check the following on link X1 before setting the output power.
• Soldered—required when setting the output power to 100 W PEP and reducing
to 85 W PEP at 26 MHz. This complies with the licensing regulations in
Australia.
• Unsoldered—required when setting the output power to 125 W PEP and
reducing to 85 W PEP at 26.5 MHz.
For PA assembly 08-05237 (2.25 to 30.0 MHz or 1.6 to 30 MHz with option LF
fitted), link X1 must remain fitted.
Setting the output power
q Ensure the Exciter output is connected to J2 on the PA and Filter PCB
Assembly.
q Select any channel frequency between 4–6 MHz (test channel 8).
q Connect an average or PEP power meter with a 50 Ω dummy load to
antenna connector J1.
q Connect the oscilloscope via a 47 kΩ resistor to antenna connector J1.
q Set the oscilloscope as follows:
Timebase
500µs per division
Trigger
Auto
q Connect the signal generator to provide two-tone audio signals (700 Hz and
2300 Hz) via the test unit to the microphone socket.
q Select transmit (PTT) and adjust the two-tone level (use the level adjust on
the test unit) for microphone compression.
q Adjust the Oscilloscope "Y" sensitivity for on-screen display and adjust the
trigger for a stationary waveform.
q Adjust the two-tone balance control for good crossover display.
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