Kenwood TS-890S, Подробное руководство

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20
03 TRANSMISSION CIRCUIT
DRV Terminal
The output level from the DRV connector is approximately 0 dBm (1 mW). Power detection is performed for output from
the ANT terminal, and the output will not exceed the preconfigured level due to activation of ALC. However, the output
level will fluctuate as ALC will not be activated for the DRV terminal output if ALC signal is not input from the external
device. This output level can be configured to a level between 100% and 5% using the [ POWER] knob. To decrease the
output level to 5% or lower, turn the [CAR] knob in a mode other than SSB, or turn the [MIC] knob (microphone gain)
or [PROC OUT] knob (speech processor output level) in the SSB mode. The level for the output signal from the DRV
connector is insufficient to be transmitted directly through an antenna. Operation with a transverter or connection to the
high-gain linear amplifier allows operation in the 135 kHz band and other bands.
The diagram below shows the spurious characteristics from the
DRV terminal in the 14 MHz band. The harmonic level
also changes upon change of the level to 0 dBm, - 10 dBm, and - 20 dBm.
DRV outputs that do not pass through a low-pass filter may include a lot of harmonic components.
For transmission, eliminate such harmonic components by passing the signal through a low-pass filter as needed after
signal amplification. Also, lowering the level using the [ POWER] knob or applying the ALC signal from the REMOTE
connector to limit the DRV connector output level can help to reduce distortion.
Fig. 22 DRV Output Characteristics 14.175 MHz 0 dBm
Fig. 23 DRV Output Characteristics 14.175 MHz -10 dBm
Fig. 24 DRV Output Characteristics 14.175 MHz -20 dBm