Service manual

STP 11-25R13-SM-TG
3 - 42
Performance Steps
(7) Check that the system output noise level (frequency modulation) between 50 Hz and 15
kHz is at least 55 dB below the audio frequency level, representing 100 percent
modulation for FM and 50 dB for AM.
(8) Attenuate all spurious emissions (including harmonics, 3 MHz above or below the channel
edge) more than 60 dB below the visual transmitted power.
e. Check multichannel television sound (MTS).
(1) The MTS baseband transmission format consists of the frequency modulated main audio
channel from 50 Hz to 15 kHz, a 15.734 kHz pilot, a 50 Hz to 15 kHz stereo audio channel
centered on 2 H, a 50 Hz to 10 kHz secondary audio channel centered on 5 H, and a 100
Hz to 3 kHz professional audio channel. See Figure 3-1 and Tables 3-1 and 3-2.
Figure 3-1. MTS Baseband Transmission Format