Daniels VT-3/140-SWA2, Instruction Manual

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Audio Processor Board Instruction Manual 9-5
9 AM AUDIO PROCESSOR
9.1 Introduction
The MT-3 AM Transmitter Main Board integrates the MT-3 Front Panel Board, MT-3 AM
Audio Processor, Synthesizer or Crystal Control module and Amplifier module together to make
a working MT-3 AM series transmitter. The Front Panel Board and the Audio Processor are
soldered directly to the Transmitter Main Board while the Amplifier and the Synthesizer or
Crystal Control module are frequency band sensitive, plug-in modules. Circuitry and jumpers on
the Transmitter Main Board control the operation of the modules as well as the overall operation
of the MT-3 transmitter. Power and signal connections are made to the 48 pin type 'F' connector
on the rear of the Transmitter Main Board and are routed to the other modules. The front and
rear back plates are attached to the Transmitter Main Board and together with the extruded
aluminum shell, as discussed in the assembly section of the Transmitter Manual, form the
transmitter enclosure.
9.2 Performance Specifications
Type: MT-3 AM Series Transmitter
Compatibility: VT-3A Series Amplifier, OCT-3 Crystal Oscillator, OST-3
Frequency Synthesizer.
Modulation: 6K00A3 (Amplitude Modulation)
Operating Temperature Range: -30˚C to +60˚C, optional - 40˚C temperature test.
Operating Humidity: 95% RH (non-condensing) at +25°C.
Operating Voltage: +13.8Vdc , +9.5 Vdc Regulated.
Front Panel Control: One 3 position switch
• NORM (repeat mode)
• OFF
• KEY TX
PTT Activation: • Active to ground with or without time-out-timer;
• Microphone activated with or without time-out-timer;
• Front Panel switch:
KEY TX - without time-out-timer;
• NORM - with or without time-out-timer.
• Isolated (optional relay) with or without time-out-timer.
PTT Time-Out-Timer: Selectable from 1 sec. to 8 hrs. (factory set 5 min.).