TUNING THE ANTENNA
If you are using your antenna at frequen- cies in the range of 25 to 30 MHz, you can tune the antenna using an standing- wave ratio (SWR) meter (not supplied) and the dual tuning rings on the bottom element.
Notes:
•If you are using your antenna at fre- quencies below 25 MHz, you will need an antenna tuner (not sup- plied) to tune it.
•The antenna's coaxial cable con- nector is the best place to check your antenna's SWR, but you can also check it at the radio's coax con- nection.
Follow these steps to tune the antenna.
1.Follow the instructions supplied with your SWR meter to adjust your antenna’s SWR to the lowest possi- ble value.
SWR values of 2.0:1 are generally acceptable, with readings of 1.5:1 or lower being more desirable.
2.With the antenna assembled and mounted, slowly move the tuning rings up as you check the SWR, until you reach your desired fre- quency.
3.If the center frequency is still too low, follow the steps under “Pre- Tuning the Antenna” on Page 3 to shorten the top element by 1/2 inch. Then check the SWR again. Keep shortening the top element until you reach the desired SWR.
4.Using an SWR meter, check the SWR at the top and bottom of the band. If the SWR is higher at the top of the band than at the bottom, raise both tuning rings counterclockwise at increments of 1/4 to 1/2 turns.
5.Repeat Step 4 until the SWR is as low as possible at both ends of the band.
6.When you have set the desired SWR, tighten the tuning rings against each other by simulta- neously turning the top ring down (clockwise) and the bottom ring up (counterclockwise) to lock them.
After you have properly installed and tuned your antenna, use a watt meter (not supplied) to test the amount of pow- er your transmitter is sending to your an- tenna. If you have properly tuned the antenna, the meter should show the transmitter’s maximum output power and the SWR meter should show very low re- flected power.
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