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This completes the Receiver stage of the alignment procedure.
Transmitter Alignment:
1. Driver BIAS:
Remove the "Shorting PCB" from TP7, TP8, and TP9. Set radio to USB mode, connect current
meter to TP9 (+) and TP8 (-).
Adjust VR11 to obtain 50 mA.
2. DRIVER BIAS:
Set radio to USB mode, connect current meter to TP9 (-) and TP7 (+).
Adjust VR13 to obtain 10 mA.
3. SSB & AM RF Power:
Reconnect the "Shorting PCB" from TP7, TP8, and TP9. Connect a watt meter and a 50 Ohm
load to the antenna connector, set radio to 28.495 MHz, USB mode, mic gain to maximum. Inject
30 milivolts of 1 KHz audio into the audio input pin of the mic jack (pin 2). Set SSB power control
(VR12) to full counter clockwise position (maximum power position).
Adjust L18, L33, L40, L42, L43, and L44 to obtain maximum power output.
Adjust SSB power control (VR12) to 21 watts peak RF power output.
Change mode to AM
Adjust VR15 to obtain 10 watts RF power output.
4. Power Meter:
Set radio to 28.495 MHz, AM mode, mic gain control to maximum, meter switch to S/RF and key
the transmitter.
Adjust VR10 until the RF meter reads 10 watts
5. TX AM Modulation:
Set radio to 28.495 MHz, AM mode, mic gain control to maximum, key the transmitter. Inject 30
milivolts of 1 KHz audio into the audio input pin of the mic jack (pin 2).
Adjust VR17 to 100% modulation.
6. CW Side-Tone Signal:
Connect a voltmeter directly across the speaker, key the transmitter using the CW jack in the rear
of the radio.
Adjust VR9 to obtain 200mV across the speaker.
This completes the Transmitter stage of the alignment procedure.
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