Belar TVM-100
Belar TVM-100
The Belar Model TVM-100 Precision Aural Monitor is a wide-band TV aural modulation monitor designed to measure the total modulation characteristics of mono as well as multi-channel television transmitters.
The TVM-100 is also used as a low-distortion, low-noise main channel demodulator for driving audio monitor amplifiers and audio distortion analyzers. Wide band composite outputs are provided for Stereo, SAP, PRO and SCA monitors.
Designed to conform with the latest EIA/BTSC recommendations, the TVM-100 features a highly accurate digital modulation calibrator for mono and stereo modes. Built-in AM and FM noise measurement capability allows direct measurement of signal-to-noise ratio as well as noise due to transmitter ICPM.
Features
- Split sound and quasi-parallel detection modes
- Built-in high-accuracy digital deviation calibrator for mono and multi-channel modes
- Digital display that indicates actual deviation in kHz, with 100 Hz resolution
- Digitally selectable peak indicator, adjustable in 1% increments from 1% to 199% modulation, independent of modulation polarity
- Semi-peak and SAMPLE/HOLD peak metering characteristics
- Measurement of SAP & PRO injection levels directly in kHz deviation (with optional board)
PWM-1
The Belar PWM-1 Peak Weighting Module is an option (consisting of a circuit board with a rear-panel rotary switch) that adds peak weighting to the Peak Mod and 100% peak lights of the Belar TVM-100 or TVM-101 TV Aural Modulation Monitor.
Peak weighting is a method for allowing brief modulation peaks to be ignored by your monitor. This will generally result in your monitor indicating a lower peak modulation for a given modulation level.
The PWM-1 Peak Weighting Module can be set to ignore peaks shorter than 3, 5, 9, 15, and 20 cycles (of a 10 kHz burst) as well as Bypass (no peak weighting). The setting is easily changed by turning a rotary switch mounted on the back panel of the monitor.
The PWM-1 can ordered with your new TVM-100 or TVM-101, or it can be retrofitted to the TVM-100 or TVM-101 you already own. (It will not work with the older TVM-1 monitor.) You can add this module yourself, or you can have it installed by Belar. Please contact Belar for more details. If you already own a TVM-100 or TVM-101, make sure you provide us with the serial number when you contact us.
Technical Specifications
Frequency Range
54 to 806 MHz (specify frequency)
RF Input
1 mv to 0.2 vrms (aural)
Detected Measurement Bandwidth
30 Hz to 150 kHz
Frequency Response
±0.01 dB, 30 Hz to 50 kHz
Linear Phase Deviation
Less than ±.05°
Modulation Metering
Deviation Indication
100% @ 73 kHz and 100% @ 25 kHz, 0-133% range
Accuracy
±2%
Characteristics
Selectable: semi-peak or sample-and-hold peak
Peak Modulation Indicators
Adjustable Indicator
1% to 199% range in 1% increments
Fixed Indicator
Set to indicate @ 100%
Accuracy
±1%
Noise Measurement
Range
-38 dB to -60 dB
Test Functions
Calibrate
Provides internal standard modulation references @ 25 kHz and 73 kHz
Deviations:
Accuracy: ±100 Hz
Calibrator Accuracy
±0.1%
Deviation Meter
Indicates modulation deviation of calibrator or test signal
Zero
Provides zero deviation for signal-to-noise measurement tests
RF Level
Sets proper operating input level
Carrier Alarm Indicator
adjusted for 90% carrier level
Outputs
Wideband Composite
Two @ 1.5 vrms for stereo, SAP, PRO and SCA monitors
Main channel Audio (Program)
±10 dBm,600 ohms, balanced
Main channel Audio (Test)
5 vrms,10k ohms, unbalanced
Audio Output Specifications
Frequency Response
±0.01 dB, 30 Hz to 50 kHz
±0.1 dB, 30 Hz to 120 kHz
Harmonic Distortion
0.01%, max (SMPTE)
Signal to Noise Ratio
80 dB, min
Dimensions
5.25"H x 10.25"D x 19"W (EIA Rack Mount)
© Copyright 2000 Belar Electronics Laboratory, Inc. All rights reserved.
