Crown Low Power Transmitters - Crown Broadcast

Section 3—Operation ................................................. 3–1
3.1 Initial Power-up Procedures .............................................................................. 3–2
3.2 Power Switches................................................................................................. 3–4
3.2.1 DC Breaker.................................................................................................... 3–4
3.2.2 Power Switch ................................................................................................ 3–4
3.2.3 Carrier Switch ............................................................................................... 3–4
3.3 Front Panel Bar-Dot Displays ............................................................................. 3–5
3.3.1 Audio Processor Input .................................................................................. 3–5
3.3.2 Highband and Wideband Display .................................................................. 3–5
3.3.3 Modulation Display ....................................................................................... 3–5
3.4 Input Gain Switches .......................................................................................... 3–6
3.5 Processing Control ............................................................................................ 3–6
3.6 Stereo-Mono Switch.......................................................................................... 3–6
3.7 RF Output Control ............................................................................................. 3–7
3.8 Digital Multimeter .............................................................................................. 3–7
3.9 Fault Indicators ................................................................................................. 3–8
Section 4—Principles of Operation................................. 4–1
4.1 Part Numbering ................................................................................................. 4–2
4.2 Audio Processor Circuit Board .......................................................................... 4–3
4.3 Stereo Generator Circuit Board.......................................................................... 4–4
4.4 RF Exciter Circuit Board .................................................................................... 4–6
4.5 Metering Circuit Board ...................................................................................... 4–8
4.6 Motherboard ..................................................................................................... 4–9
4.7 Display Circuit Board ....................................................................................... 4–10
4.8 Voltage Regulator Circuit Board ...................................................................... 4–11
4.9 Power Regulator Circuit Board ........................................................................ 4–12
4.10 RF Driver/Amplifier (FM30) ............................................................................. 4–12
4.11 RF Driver (FM100/FM250)............................................................................... 4–13
4.12 RF Amplifier (FM100/FM250) .......................................................................... 4–13
4.13 Chassis ........................................................................................................... 4–14
4.14 RF Output Filter & Reflectometer..................................................................... 4–14
4.15 Receiver Circuit Board Option ......................................................................... 4–15
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