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TECHNISONIC A711L SeriesTECHNISONIC A711L Series
3rd Generation Advanced Analog audio.
Full fail-passive capability.
7 Radios + PA, with 1-button transfer.
Tactile, lighted controls. Cleaner layout. Tone alerting. Plug compatible.
TECHNISONIC A711L seriesTECHNISONIC A711L series
Cosmetic Options. NVG + flexible light. Powersonix PA
capability. Nifty PA options. Latent features. Ideal mate to the
TDFM-7300. Address integrated
NAV/COM packages.
TECHNISONICTECHNISONIC
Coming soon, the ARTS-100 system. A genuine “wahoo” test moment.
http://til.ca short and sweet.
[email protected] any time for audio questions.
Available from Dallas Avionics.
TECHNISONICTECHNISONIC
GET TRAINED! Saturday at 1:30pm
Prizes for correct answers!
See us at BOOTH 103 / 801
Thank you!
Noise is the Noise is the EnemyEnemy
Installation costs and time are momentary…
But a bad install is forever.Take the time to get everything as
right as possible.Understanding noise origins is
critical.
Types of NoiseTypes of Noise
In-band audio frequency noise.Cross-talk
Signal contaminationInverter/Generator Contamination
Types of NoiseTypes of Noise
Out-of-Band RF Sources:AM Comms
HF/SSBFM Comms
RF ProblemsRF Problems
Ship Issues can be multi-modal:Radio to Radio Interference
HarmonicDirect
Radio to Audio line rectificationAntenna Induced Standing Waves
Mechanical-RFMechanical-RF
The Main Rotor will modulate outgoing transmissions, and incoming reception, and change reflected power.
Antenna PLACEMENT is everything to fix this.
Antenna IssuesAntenna Issues
Bottom Mounts work best for AM Comms on helicopters.
Spacing & ProximitySpacing & Proximity
There’s rarely enough room in general aviation aircraft...
10 kg in a 10 kg in a 5 kg5 kg box box
Sometimes it’s just not that easy…
Audio WiringAudio Wiring
Wiring topology and routing has a large bearing on audio system performance.
No amount of shielding can overcome design limits.
Audio WiringAudio Wiring
Access/A (floating ground) technology can provide a 20-30dB improvement in noise and cross-talk over even high end grounded systems.
That is 100-1000 times better.
Audio WiringAudio Wiring
Grounded audio returns are highly subject to GROUND LOOP noise.
This style interconnect was an early method of saving weight, complexity and wire, but offers the worst possible performance.
Ground LoopsGround Loops
How we wish aircraft worked:
Ground LoopsGround Loops
What really happens:
Ground LoopsGround Loops
The “frame ground” is alive with voltages caused by different loads.
Ground LoopsGround Loops
Attaching audio returns to ground contaminates the audio signal with every load current flowing through the airframe.
These induced voltages can be VERY large, and are a real problem especially for low level audio lines like microphones.
Ground LoopsGround Loops
Ground currents also inject CROSS-TALK, as every audio line returned though ground becomes mixed with every other audio signal.
Ground LoopsGround Loops
The answer is to LIFT audio lines from the airframe ground, and process them as floating signals.
This improves both noise and cross-talk significantly.
Ground TopologyGround Topology
Floating TopologyFloating Topology