Figure 3-10. Transceiver (Vhf And 700-800 Mhz) Block Diagram; Figure 3-11. Transceiver (Uhf1 And 700-800 Mhz) Block Diagram - ASTRO APX 7000 Basic Service Manual

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3.2.2 Transmitting
When the radio is transmitting, microphone audio is digitized and then processed by the DSP and
sent to the Trident IC
processes the SSI data for application to the voltage controlled oscillator as a modulation signal.
RF Switch
TX Buffer Amp
RF Switch Matrix
Figure 3-10. Transceiver (VHF and 700–800 MHz) Block Diagram
RF Switch
TX Buffer Amp
RF Switch Matrix
Figure 3-11. Transceiver (UHF1 and 700–800 MHz) Block Diagram
(see Figure 3-10
Driver Amplifier
Loop Filter
Trident IC
VCO Module
VCO Module
VCO Module
Driver Amplifier
Loop Filter
Trident IC
VCO Module
VCO Module
VCO Module
VCO Module
Basic Theory of Operation: Analog Mode of Operation
to Figure 3-15) via the SSI interface. The Trident IC
Switch
FET VHF
Harmonic Filters
FET 700/800
SP3T RF Switch
To RX
Ref. Oscillator
TX SSI from Vocon
Switch
FET UHF1
Harmonic Filters
FET 700/800
SP3T RF Switch
To RX
Ref. Oscillator
VCO
TX SSI from Vocon
Log amp Power Detector
Digital RF Attenuator
SP2T RF Switch
Coupler
Rev Power Detection
Log amp Power Detector
Digital RF Attenuator
SP2T RF Switch
Coupler
Rev Power Detection
To Antenna
To RMT Port
To Antenna
To RMT Port