The parts of the aircraft’s radio system are
- The Transceiver – this is s a combined radio transmitter and radio receiver
- Selector panel- often built onto the face of the transceiver in one box these days
- The aerial – which come in all shapes and sizes both internal and external
- The input output sockets to plug head sets into
- Cabling for power and to the sockets
- A radio fuse or circuit breaker
- An avionics master switch or radio master switch
- Power supply from the battery or generator
Garmin Selector Panel – Transceiver
This selector panel is typical of a modern radio transceiver in an RAA aircraft. Note it has two frequencies showing. This allows you to listen to 2 frequencies at one time or switch between two frequencies easily. An example of its use is when flying near 3000 feet and you need to be monitoring 2 stations FIA and Multicom.
The power comes on via the avionics or radio master switch. Its volume is the knob on the left.
The arrow button allows you to quickly change from the left to the right frequency. Note the numbers actually change so the live frequency s on the left. If you broadcast it will always go out on the channel indicated on the left. To listen to both,simply press the monitor (mon) button.
The right hand knob controls the frequency. It changes the frequency on the right. The big part of the knob changes the numbers before the decimal and the small part changes the numbers after the decimal. Once you had your new frequency in, you would hit mon for both or the arrow button to make the new frequency the live frequency.
When you pull that knob out it becomes a squelch control. The squelch controls the sensitivity of your radio and eliminates background noise. Too sensitive and you will hear every noise and it will sound like the ocean the entire time. Go the opposite way and you won’t hear a thing, not even radio calls.
Transmit Button / Intercom
All RAA aircraft with a radio will have a transmit button. This is generally mounted on the control stick or yoke, the control bars in a trike or a handheld microphone. When You talk through a microphone headset the other people in your aircraft can hear you and they can talk back, this is known as an intercom. Only when you press the transmit button does your voice go out over the radio to other aircraft or ground stations.
The microphones come in hand held or boom of the side of your headset. Its important to read your documentation to make sure the gap between your lips and the mic is appropriate.
Speakers come in three main types, a cockpit speaker which broadcasts noise through the entire cockpit, much like a stereo speaker at home. Headset speakers which come in many variants, but basically over ear and in ear types. Most modern headsets have noise cancelling in their top range models. For career pilots or pilots who do longer flights these can reduce fatigue and protect the ears from constant noise.