User Manual

Technalogix Ltd. TM-100 Modulator
5
3.0 DESCRIPTION AND SPECIFICATIONS
General Description
The high output modulator eliminates the need for preamplifiers prior to the
power amplifier system. The modulator processes baseband audio and video
information to provide an IF output consisting of a visual IF carrier at 45.75 MHz,
using amplitude modulation, and an aural IF carrier at 41.25 MHz, using
frequency modulation. An internal upconverter translates the modulator circuitry’s
IF carriers to VHF and UHF television frequencies. All operating controls are
located on the front panel, as described in a later section. An aural loop through
is provided to properly set transmitter power.
Standard Features
• Totally microprocessor controlled with self-diagnostic monitoring.
• Selectable output channels:
§ Standard Broadcast VHF 2 – 13, UHF 14 – 60, T7 – T13
§ HRC channels 1 through 118
§ ±10 kHz offsets
• SAW filtered IF designed for adjacent channel operation.
• + 60 dBmV output using low distortion hybrid amplifiers.
• Synthesized oscillators – crystal referenced phase locked.
• Bar graph modulation and digital LED readout.
• Internal switch selects standard or HRC output.
• Surface mount technology construction.
• RF muted during tuning.
• Optional aural sub-carrier and baseband audio input
• Phase lock loop FM audio.
• BTSC stereo compatible.
• External separate audio/video and composite IF loop-through.
• RS-232 control option (daisy-chain capable)
• Sound carrier level adjustable –10 dB to –20 dB.
• Video delay predistortion network meets FCC 73.687.
• High stability TCXO, ± 250 Hz
• Non-volatile memory retains channel selection after power loss.
• Video Detection turns off carrier in event of loss of video.