APRS Hardware and electronics

Single-board computers

• Raspberry Pi

Sound Cards

• CMedia CM106 USB sound adapter

Pre/De-emphasis filters

• Opamp-filters homebrew filters to compensate for radios that do not support Pre/De-emphasis

PTT on Raspberry Pi

• GPIO_pin_on_the_RPi_to_trigger_PTT

Realtime Clock (RTC) module

• RTC_on_RPi