TUNING
1. Select the band and frequency of desired operation.
2. Set INPUT, OUTPUT, and BAND SWITCH controls to the suggested settings before
applyng transmitter power. Actual settings may vary from antenna to antenna.
3. Set up your transmitter to a low power output. If your transmitter has a TUNE
position, select that position.
4. If you use a linear amplifier, set it to STANDBY. Do not use the linear amplifier
until the DU 1500T is tuned.
WARNING: Do not exceed 1500 W (Single tone or Keydown).
5. Set POWER RANGE switch to 200W.
6. Set OUTPUT SELECTOR switch to BYPASS, or to the position matching your antenna
connection. To tune your antenna, the switch selection must be set to: COAX 1 TUNED
COAX 2 TUNED, or BAL.LINE+COAX 1. Selecting COAX 1 DIRECT, COAX 2
DIRECT, or BYPASS.
7. Rotate the INPUT and OUTPUT controls for maximum noise or signal as heard
on your receiver.
8. Key your transmitter and adjust the power level for a reading of 50 to 100 watts on the
FORWARD scale. Adjust the INPUT and OUTPUT controls for a minimum
REFLECTED reading while maintaining a FORWARD reading of 50 to 100 watts using
your transmitter power control.
9. Read the SWR on the red scale at the point where the two needles intersect. Repeat step
8 until the lowest SWR reading is obtained. The SWR should be 2:1 or lower.
NOTE: This procedure takes patience the first time. The INPUT and OUTPUT
controls vary the capacitors and provide fine adjustments.
