Automatic Tuning Operation - JRC JRL-2000F Manual

BASIC OPERATION
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6.3 Automatic Tuning Operation
During Automatic Tuning operation, the JRL-2000F matches the currently selected antenna
to the frequency of transmission. The matching data and antenna selection is then stored into
memory for instant recall at a later time.
There are two functions of the Automatic Tuner portion of the JRL-2000F:
VSWR Matching
-
Matches the antenna VSWR and sets the. load in the final stage of the
exciter and linear amplifier to 50R.
Low Pass Filter (LPF)
-
The LPF attenuates undesired harmonics contained in the output
from the power amplifier.
After the tuning operation is completed, the data is stored in memory according to the JRL-
2000F band assignments (see section 6.3.2). It is necessary to perform the automatic tuning
operation for each band or sub-band.
For example, the 14 MHz band is divided into four sub-bands. Therefore, automatic tuning
must be done within each of these sub-bands in order to cover the entire 14 MHz band.
Since antenna selection data is also stored, tuning must be done after selecting an antenna.
Tuning data remain stored in memory until:
Automatic tuning within the same sub-band is performed again; or
The data is deleted from memory (see section 7.1).
Important
Do not operate the JRL-2000F in any band or sub-band that has not been previously
tuned. If excessive VSWR is present, one or more of the built-in protection circuits
may be activated.