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Brian SmithAug 18, 2025
What to do if my Raymarine Radio does not transmit (TX)?
- Llisa99Aug 18, 2025
If your Raymarine Radio is not transmitting, check the PTT switch on the handset (S727). Then, inspect the PTT control circuit, focusing on TXD data at Q705, pin 27 of IC 706, and the PTT signal at PC304, PC306, PC308 and RXD data at Q319-320. Also, verify the T8v line at Q31 output and the PLL signal (5V at Q32 input, IC305 pin79). Ensure PLL unlock status at IC5 pin3 (unlock=51) and review the PLL circuit. Potential defective components include handset parts like IC708, Q701, Q705-707, PC701, PTT Sw; CPU PCB parts like IC305, PC304-309 Q316-321, D307-312; and RF PCB parts like Q31-32 and the PLL circuit.










