Technical data

VHF/AM RADIO FSG 2T

2 General Description

18 FAV_D10048 June 2014

2.10 Some words about Microphones

IMPORTANT

a) Radio performance and system reliability significantly depend on quality

acoustic accessories, and their proper audio leveling adjustments. Please

avoid use of low quality / low performance accessories.

b) After installation completion, optimized acoustics performance requires

proper mike audio system selection and its appropriate level adjustment

(non-amplified dynamic, or Standard Carbon Microphone(s) system).

c) Since the radio FSG 2T has got two (2) separate microphone inputs, it is

possible to connect and adjust different microphone types / techniques on

separate MIC inputs.

Furthermore two microphones can be connected in parallel to one input,

but then

 make sure that only microphones of identical type / characteristics

may be interconnected in parallel and appropriately together adjusted/

matched.

If a microphone is, however, removed, then the setting is too sensitive

for the remaining microphone (because of a missing attenuation by

the 2nd mike) and therefore should be adjusted optimally once more

in noisy aircraft.

d) Dynamic microphones require shielded wiring and galvanic separation of

mike grounds from any other signal ground (e.g. DC input / DC output,

Dimmer, Speaker, Phone, PTT, and external AF input ground).

e) Standard Carbon / compatible amplified microphones may employ

Dynamic or Electret acoustics transducers. Amplified microphone ground

may be connected together with other grounds, e.g. for DC input /

switched output, speaker, phone, PTT, dimmer, external audio input.

f) Operation of amplified microphone systems close to the RF radiating

antenna (on portable case or located close to the cockpit) may be heavily

interfered from own radiated strong antenna RF field strength and become

unstable, oscillates or causes modulation distortion. Verify such effects,

which are possibly caused by RF, by replacing the radiating antenna

against an artificial antenna / RF dummy load temporarily.