Vectronics VC-300DLP - Manual (Page 6)

VC-300DLP Antenna Tuner Owner's Manual
6
5. Set OUTPUT SELECTOR switch to the proper selection on the TUNED side of the switch.
Selecting any of the DIRECT positions by passes the tuning circuitry altogether.
6. Rotate the TRANSMITTER, ANTENNA, and INDUCTOR controls for maximum noise or
signal as heard on your receiver.
7. Key your transmitter and adjust the power level for a reading of 40-50 watts on the
FORWARD scale. Adjust the TRANSMITTER, ANTENNA, and INDUCTOR controls for
a minimum REFLECTED reading while maintaining a FORWARD reading of 40-50 watts
using your transmitter power control.
8. Read the SWR on the red scale at the point where the two needles intersect. Repeat step 7
until the lowest SWR reading is obtained. The SWR should be 2:1 or lower.
Note: This procedure takes patience the first time. The transmitter and antenna controls
vary the capacitors and provide fine adjustments. The inductor control provides
course adjustment. If the SWR can not be reduced to the lowest reading, try
increasing or decreasing the reading of the transmitter control. Then, try to null the
antenna control for the lowest reading. You may want to try reversing this procedure
by increasing or decreasing the antenna control and nulling the transmitter control.
Always perform these adjustments at low power.
9. When you have tuned your antenna to the best SWR, record the settings of the
TRANSMITTER, ANTENNA, and INDUCTANCE controls on the chart on the preceding
page for future reference. When you retune, use these settings as your starting point.
NOTES
1. An SWR of 1:1 is best, but an SWR as high as 2:1 may be acceptable. Check your
transmitter manual for details.
2. If you can not get an acceptable SWR, lengthen or shorten your antenna and/or feedlines and
retune.
3. If you get low SWR readings at more than one setting, use the setting that:
•
Gives the highest FORWARD power reading.
•
Gives the lowest REFLECTED power reading.
•
Uses the largest capacitance (highest number) on the TRANSMITTER and ANTENNA
controls.
4. Any time a new or different antenna is connected, it is necessary to repeat the tuning
procedure for each antenna.