Four State QRP Group Cyclone 40, Инструкция по эксплуатации

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Next, the transmit-mixer filter transformers must be peaked. Unscrew the PTO
screw until a second birdie is heard in the headphones. This occurs at
approximately 3.930 MHz PTO frequency, and serves as a mid-band indicator.
Key the rig. With L4 not installed, the rig may be keyed continuously with no risk
of damage to any component. With your digital voltmeter, observe the voltage
on TP1 and TP2, which are the final amp drive signals. They should both be in
the 2 to 3 volt range. If the reading is erratic, it may be due to RF from the drive
signal entering the meter. You may add a 10k resistor between the test probe of
the meter and the test points to reduce the effects of RF.
While monitoring TP1, adjust the R11 BALANCE pot until the TP1 reading is 2.0
volts. Then, using your non-metallic alignment tool, alternately adjust T3 and T4
several times until the DC voltage at TP1 is maximized. The peak is fairly sharp,
and may require patience to find.
When the voltage at TP1 is maximized, re-adjust the BALANCE pot until the
voltage at TP1 matches that at TP2. Unkey the transmitter.
Press the FREQ button, and note the four digit count. Key the transmitter, and
while it is keyed, press the FREQ button. Note the four digit count. The two
numbers should differ by 20 to 40. If it is much larger than this, it is an indication
that T3 and T4 are tuned to a spur frequency. Repeat the T3-T4 alignment step,
and re-BALANCE.
Next, the transmit/receive frequency offset is adjusted. This is done in two
processes. Press the FREQ button, and record the four digit count output.
Then, when keying the transmitter, press the FREQ button, and record the
count. The TX count should be higher than the RX count by 20 to 40. One at a
time, solder-bridge in a section of the offset capacitor, which is set of copper
pads on the bottom of the board next to the PTO inductor. Start from the one
closest to the center of the board, and add the next one out. Measure the
difference in FREQ count between RX and TX, and if the TX count is higher
than the RX count by more than 5, add another section of the offset cap.
Finally, fine-tune the offset by adjusting the OFFSET pot R16 until the four digit
frequency count matches on transmit and receive.
If you prefer to only hear a three-digit frequency count, it is possible to disable
the final, hundred-Hz-count digit by installing a wire jumper at JP2