Daniels Electronics MT-3 Series, Инструкция по эксплуатации

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Transmitter Alignment
28
MT-3 FM Transmitter Mainboard Instruction Manual
IM20-MT3TXMN
transmitters with Pre-emphasis and CtCSS Subtone
Section a: Balanced and Subtone audio Setup
Step Reference Action Desired Results Notes
1. R2 (Mic I/P)
R29 (Deviation)
R31 (Balanced)
R38
(Compress)
R42 (Subtone1)
R63 (Mic Comp)
R36 (TCXO)
Turn Fully CW.
Turn Fully CW.
Turn Fully CW.
Turn Fully
CW.
Turn Fully CW.
Turn Fully CW.
Turn Fully CCW.
AF Filter: Low Pass
5 kHz or 15 kHz
2. Balanced Input
P1-1 and P1-2
Set AF tone freq,
level and filter.
AF Gen:
1.8 kHz @ +10 dBm
3. R29 (Deviation) Adjust R29 for deviation.
Do not re-adjust.
± 4.4 kHz
4. Subtone 1 input Apply tone. AF Gen:
1 kHz Tone @ -18 dBm
5. R42 (Subtone1) Adjust and measure. ± 500 Hz Deviation Monitor
6. OST-3H035-(2-Port)
OST-3H045-(2-Port)
Change AF Gen. freq. AF Gen:
40 Hz @ -18 dBm
7. R36 (TCXO) Adjust and measure. ± 500 Hz
8. Subtone 1 input Change AF Gen. freq. AF Gen:
300 Hz @ -18 dBm
9. Deviation Monitor Should measure. 500 Hz Tolerance on this
measurement is ± 50Hz
10. Deviation Monitor Sweep AF Gen. freq.
between 67 Hz and
250 Hz . Measure
resultant deviation.
± 300 Hz to 700 Hz
11. Balanced Input
P1-1 and P1-2
Change frequency and
level.
AF Gen: 1 kHz Tone @
+10 dBm
12. R38 (Compress) Adjust and measure. Distortion Analyzer
AF Filter: 15 kHz
4.0% THD
13. AF Gen. Change level 1 kHz Tone @ -8 dBm
14. R31 (Balanced) Adjust and measure. ± 3 kHz Deviation Monitor
15. AF Gen Change level. 1 kHz Tone @ -18 dBm
16. R31 (Balanced) Measure and confirm. ± 1 kHz Tolerance on this
measurement is ± 50 Hz