Agc Circuits; Analog Agc Circuits - Kenwood TS-890S In-Depth Manual

RECEPTION CIRCUIT 02

AGC Circuits

Analog AGC Circuits

To achieve high receive dynamic range characteristics, an analog AGC circuit is used together to make the A/D
converter work to its performance limit. The AGC circuit is required to have low noise and a wide dynamic range, wide
control range, and linearity to the control. The TS-890S implements high-precision AGC response characteristics with
the combination of an AGC circuit in which a dual-gate MOSFET is used and the correction process made by DSP. The
"AGC Circuit with a Dual-Gate MOSFET" is shown below:
Fig. 7 AGC Circuit with a Dual-Gate MOSFET
The "AGC Response Characteristics to a Control Voltage" graph below shows the AGC response characteristics to
a control voltage in the circuit configuration with a dual-gate MOSFET. Sufficient control range, dynamic range, and
linearity are secured.
Response Characteristics
Fig. 8 AGC Response Characteristics to a Control Voltage
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