hune H-200, User Manual

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# Decoder (U26)
# Operational Amplifier (U9, U19)
# Transmit VCO/ Receiver First LO VCO (VCO1)
# Phase locked Loop
# Power Amplifier (U4)
# Driver Amplifier (U6)
1. Antenna
Antenna is for optimal receiving of transmission signal from base station.
Reduce damage of weak signal under general external environment and voltage from
device to a minimum.
2. Antenna Switch
The RF switch is it can be controlled with positive, negative or a combination of both
voltages. Some standard implementations include antenna changeover,
Transmit/Receive and diversity switching over 3W.
3. AGC (Automatic Gain Controller) Circuit
Level of signal which device receiving should maintain regular signal and AGC is for
Power control of device.
4. LNA (Low Noise Amplifier)
LNA is used for reducing noise to a maximum for optimal signal and amplify signal
that need to receive separately.
5. RF SAW (Surface Acoustic Wave) Filter
RF Saw Filter is used for band pass for the signal of receiving frequency and reduce
other signal except receiving frequency in order to receive selected receiving frequency
of Pager.