MFJ MFJ-207, Инструкция по эксплуатации

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MFJ-207 Instruction Manual HF 10-160M SWR Analyzer
EASY START INSTRUCTIONS
II. HOW TO MEASURE THE FREQUENCY AT WHICH THE ANTENNA HAS
THE LOWEST SWR.
1. Connect the antenna as discussed in step I, 1 or 2.
2. Turn the BAND switch to the appropriate band.
3. Adjust the TUNE control throughout its range until the SWR meter reads its
lowest value. Record the frequency on the frequency meter. Record the SWR
on the meter. For added frequency accuracy hook up a frequency counter or
refer to Appendix A.
4. If you do not obtain a low SWR on any frequency, turn the Band switch to
another band and repeat steps 1-3 above. Don’t be surprised if your antenna
does not show a 1:1 SWR on any frequency. Many antennas can be tuned to
obtain a 1:1 SWR, but will never show a 1:1 SWR without an antenna tuner.
III. Adjust the Antenna for 1:1 SWR.
1. Again connect the antenna as discussed in step I, 1 or 2.
2. Turn the BAND switch to the appropriate band.
3. Turn the Frequency TUNE knob until the pointer is on the frequency at which
you want to tune the antenna.
NOTE: For accuracy, use a frequency counter attached to the FREQ. Output on the SWR
analyzer or zero-beat against your receiver. See Appendix A.
4. Read the SWR on the meter. If the meter reads other than 1:1 SWR then
adjust your antenna until the antenna read 1:1 SWR or the lowest value
obtainable.
NOTE: The MFJ-207 can tell you whether the antenna element are to short or too long.
If you find the resonant frequency of the antenna is lower than the frequency
you wish then the elements are too long. If the resonant frequency is higher
than you want then the elements are too short.
HINT: If you are adjusting an antenna for the first time, it is recommended that you start
with elements a little too long, then shorten to resonance. Again the SWR for
your particular antenna may never get as low as 1:1. Always adjust for the
lowest reading.