Park Air T6T, Руководство пользователя

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Chapter 2. AM-Voice Specification
This chapter gives the transmitter's specification applicable to AM-voice operation.
RF CHARACTERISTICS
Channel spacing 25 kHz, or 8.33 kHz across the frequency band 118 to
136.975 MHz.
Spurious outputs Spurious outputs are below -46 dBm. Spurious outputs
are measured greater than 500 kHz from the carrier
frequency and with a modulation index below m = 0.9.
Transmitter rise time 90% of full power is reached within 20 ms of keying the
transmitter.
Transmitter decay time The output power decays by at least 20 dB 5 ms after
the keying potential is removed.
MODULATION CHARACTERISTICS
Modulation depth Adjustable up to 100%.
Hum and noise Greater than 45 dB below the signal level. Measured
within a 15 kHz bandwidth with the carrier modulated by
a 1 kHz signal and at a modulation depth of 90%.
Frequency response With 25 kHz channel spacing the variation in frequency
response, with reference to a 1 kHz signal, is within
+1 dB and -3 dB across the frequency range 300 Hz to
3.4 kHz. The response is better than -20 dB at 100 Hz,
and less than -30 dB at 5 kHz.
With 8.33 kHz channel spacing the variation in
frequency response, with reference to a 1 kHz signal, is
2 dB and -4 dB across the frequency range
350 Hz to 2.5 kHz. Frequencies above 3.2 kHz are
attenuated by at least 25 dB.
Distortion With a 90% modulation depth, distortion is less than 5%
at frequencies between 300 Hz and 3.4 kHz.
Residual FM With a 1 kHz signal set at 80% modulation applied to the
transmitter's audio input, the unwanted frequency
modulation is less than 500 Hz.
VOGAD The VOGAD has an operational range of 30 dB with the
threshold set relative to the line level setting. Within the
VOGAD range, the modulation depth is maintained
within 10% of the set level.
VOGAD has an attack time between 20 and 50 ms
measured with a 10 dB step to 15 dB into VOGAD, and
a decay time greater than 2 seconds.
T6T AM-Voice Operation Section 2
Page 7