[Antenna] → [Rx/Tx Switch] → [Preselector] → [LNA] → [Mixer] → [IF Filter] → [Demod] → [Audio Amp] → [Speaker] ↑ [Microphone] → [Audio Preamp] → [VCO Modulation] → [PLL Synthesizer] ← [Reference Oscillator] ↓ [Driver PA] → [Final PA] → [LPF] → [Antenna]
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Here is the organized content structure for the . [Antenna] → [Rx/Tx Switch] → [Preselector] → [LNA]
| Component (UHF Model) | Replacement Part # | Notes | | :--- | :--- | :--- | | | MRF646 or PF0443T | Requires thermal paste. | | Audio Amp | TDA7256 | Common failure (distorted audio). | | Voltage Regulator | MC33269T-5 (5V) | Check if radio intermittently resets. | | Microcontroller | MC68HC11E9 | If corrupt, needs donor codeplug. | Here is the organized content structure for the