The AA39-187 is a single military headset adapter, consisting of a 5Ω dynamic mic to civil aviation 150Ω mic adapter, with an 8Ω to 600Ω transformer for phones matching. The AA39-187 is a small, remote mounted metal unit with a D-sub connector. Designed to operate from standard mic bias, supplied by the aircraft radio and intercom system.
规格：
Weight:
0.35 lb / 0.16 kg
Input signals
Mic bias:
Nominal Bias Voltage: +12 Vdc
Maximum Bias Voltage: +16 Vdc
Minimum Bias Voltage: +9 V
Audio level:
250µ Vrms for mic input
7.7 Vrms for phones input
Input current:
10 mA Max. @ Min Bias Voltage
Impedance:
5Ω ± 1Ω for mic input
300Ω ± 10 % for phones input
Circuitry type:
Balanced input for mic
Balanced transformer input for phones
Output signals
Gain:
Min. 1000 or 60 dB for mic amplifier
Min. 8.5:1 ratio for phones transformer
Circuitry Type:
Single ended output for mic
Balanced transformer output for phones
Frequency response:
< 3 dB from 350 Hz to 6000 Hz. for mic channel
< 3 dB from 350 Hz to 6000 Hz. for phones channel
Distortion:
< 10% THD @ Rated power output
< 3% THD @ 10% Continuous output
Audio Noise Level:
Without Signal: < -50 dB from rated output
特征：
Provides adaptation for dynamic to civil headsets
Single headset adapter
D sub connector
Powered by mic connection
1 mic input - 5 ohms / 0.250 mV
1 phones input - 600 ohm / 7.7 V
1 mic output - 0.25 V into 150 ohms
1 phones output - 0.9 V into 8 ohms
