The SI4735 requires a specific software patch loaded into its RAM upon bootup to enable Single Sideband (SSB) mode. If your radio fails to enter SSB, the schematic will help you trace the data line from the EEPROM/MCU to the SI4735. 2. RF Front-End and Antenna Switching
If you are interested in trying to mod your unit, I can provide more details on the ferrite rod upgrade process or help identify the best test equipment for aligning the trimmers.
Clearly read resistors, capacitors, and inductor values without guessing blurred text.
Signals pass through an ESD protection diode network and an electronic switching matrix (often using switching diodes or a dedicated bus switch IC) to route the external or internal whip/ferrite antenna to the correct input pin on the SI4735. 3. Audio Amplification Stage