15
1-9-1, NEUTRALIZATION PRE-TUNE
Power up in the safe mode. Set the band switch to 21. Set the VFO dial to 360. Set the RF LEVEL to 8. Switch
to CW and adjust the DRIVER TUNE and FINAL TUNE for max power out. Reduce the RF LEVEL as needed
to keep the power out at 45 - 65 watts. (you may have to peak L6 and L16 to get power peak.) Once you have
tuned up
you will not readjust the DRIVER TUNE or the FINAL TUNE
throughout the rest of the
neutralization process.
1-9-2, NEUT. SET UP
Power down the transmitter.
•
Remove PA cover.
•
Locate the wire connected to the base of the plate choke L27 and disconnect
it. Tape the end of the wire or otherwise protect it from touching anything.
•
Locate R77,1.8K 1w resistor. Disconnect it at the terminal strip end.
Power up in safe mode and insure the RF LEVEL is at minimum. Allow enough warm up time to insure the PA
tubes are up to max temp. Connect the scope to ungrounded end of L29. Switch to CW and advance the RF
LEVEL until you get good signal on the scope. Adjust C77 for minimum signal. Some advance of the RF
LEVEL and the scope gain will be needed as you approach the null.
This completes the neutralization process.
1-10, CARRIER DRIVE LEVEL
The carrier oscillator ckts have enough drive to drive the transmitter to well over 200 watts. However, the audio
phasing and modulation ckts are only designed to operate efficiently at the 100 to 130-watt level. It is critical
that T2 be set to the proper level. Select the center of any band.
1-10-1 CARRIER LEVEL ADJUSTMENT
Set the transmitter to the “save” mode allow 10 minutes warm up. KEEP THE TRANSMITT TIME TO A
MINIMUM. It is recommended to plug in a telegraph key and only go key down in short bursts while making
the adjustment. This also saves wear and tear on the function switch.
•
Set the RF LEVEL to 8.
•
Key the transmitter and tune the DRIVER TUNING and the FINAL TUNING max power.
•
Unkey and rest the finals for a few seconds.
•
Key the transmitter and tune T2 for 130 watts output.
•
Unkey and rest the finals for at least 20 seconds.
•
Key the transmitter and check power out make readjustment of DRIVER TUNING and FINAL
TUNING. If the power out exceeds 130 watts back it off with a detune of T2.
•
Key check power, unkey and rest several times to insure stability of adjustment.
NOTE: At this point, if you have followed the process as written all the major systems have been tested
and proven. You are about to start the modulation and carrier suppression test and evaluation. There are
components that have not been tested at this point. They are: V4, T7, and some switching functions of the
FUNCTION and OPERATION switches. If you are not able to generate SSB power in the section 1-11
check V4, T7 and the switches. So far, we have worked around the VOX, ANTI-TRIP and AALC
functions. Tests and adjustments of these subsystems are covered in section 2.