NT 250 Technical and Maintenance Manual | NicomUsa Inc |
COMPOSITE OPERATION |
|
Composite inputs | four total, 1 for MPX and 3 for SCA |
MPX input | 1 unbalanced bnc connector |
MPX input impedance | 2 K ohms |
MPX input level | 3,5 V |
Composite FM unweighed S/N ratio | > 78 dB below ± 75 Khz deviation at 400 Hz |
| measured in a 30 Hz - 100Khz bandwidth with |
| 75 usec |
Composite Total Harmonic Distortion | 0.05 % typical |
Composite Intermodulation Distortion | 0.05 %, measured with a 1 Khz and a 1.3 Khz |
| tone, 1:1 ratio, at 100% modulation |
Baseband | 30 Hz - 60 Khz within 0.15 dB |
Crosstalk | main to stereo subchannel and stereo subchannel |
| to main > 55 dB ( 60 dB typical) |
SCA Inputs | 3 unbalanced BNC connectors |
SCA Input Impedance | 10 K Ohms |
SCA Input Levels | 0 dBm (775 mV rms/ 2.2 V |
| ± 75 Khz deviation, adjustable |
SCA Amplitude Response | ± 0.8 dB, 40 Khz to 100 Khz |
Crosstalk | 67 Khz SCA to main or to stereo subchannel >65dB |
| 92 Khz SCA to main or to stereo subchannel >70 dB |
MONOAURAL OPERATION |
|
Audio Input Impedance | 600 Ohms balanced or unbalanced; 50 dB common |
| mode suppression |
Audio Input Level | 0 dBm (775 mV rms/ 2.2 V |
| ± 75 Khz deviation, adjustable |
FM S/N Ratio | > 70 dB below ± 75 Khz deviation at 400 Hz |
| measured in a 30 Hz - 20Khz bandwidth with |
Audio Frequency Response | 75 usec |
± 0.8 dB, 30 Hz to 15 Khz | |
Intermodulation Distortion | 0.05 %, measured with a 1 Khz and a 1.3 Khz |
| tone, 1:1 ratio, at 100% modulation |
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