AMMA-2 AM Modulation Monitor

Belar AMMA-2 AM Modulation Monitor front panel

Description

The AMMA-2 is a DSP based, microprocessor-controlled, digital AM modulation monitor/analyzer that precisely measures positive and negative peak modulation, peaks per minute, average peak modulation, modulation density, and more. In addition to monitoring standard AM modulation, the AMMA-2 accurately monitors modulation-dependent carrier level (MDCL) AM transmissions. During MDCL broadcasts, the RF carrier level becomes a dynamic component of the AM signal. The AMMA-2 tracks the carrier, capturing the highest and lowest values of the carrier level, as well as the decibel ratio of the carrier high/low. Modulation readings are referenced to the carrier level appropriate for the MDCL system in use. The optional remote meter panel displays positive modulation, negative modulation, and carrier level simultaneously on three large analog meters.

The AMMA-2 features user-defined parameters and settings for maximum flexibility. Two large UP/DOWN MENU keys are used to cycle the 16-character alphanumeric display to the desired menu; the UP/DOWN PARAMETER keys are then used to select the desired setting. The unit configuration may be saved to the on-board non-volatile memory so the settings are retained in the event of a power loss.

A noise menu selection displays RMS-detected SNR in decibels (flat or de-emphasized) on the front panel.

A carrier cutoff indicator consisting of three front panel LEDs continuously monitors the approach of negative modulation to carrier cutoff.

A unique "Normal Modulation" indicator shows when modulation is falling within user-defined parameters.

A built-in Audio Sentry audio failure alarm alerts you to loss of modulation or drops in modulation level.

An RS-232/RS-422 port allows the AMMA-2 to be accessed v ia personal computer. The ASCII command set, documented in this manual, provides an easy way for users to write their own command and control software. Alternately, the AMMA-2 will be supported in the future by The Wizard Software, which provides unit control and graphing and logging capability for all the AMMA-2 measurements.

A remote alarm connector, consisting of 8 pairs of relay contacts, provides alarm status information for hard-wired applications. NRSC de-emphasis may be selected internally by moving a jumper plug.

Features

Specifications

RF Input

RF Frequency Range
250 kHz to 30 MHz
RF Tuning Increments
1 kHz
RF Sensitivity
1 to 10 Vrms
RF Input Impedance
500Ω or 50Ω, internally connected

Metering & Display

Accuracy
1.0%
Negative Modulation Display
Large 3 digit LED
Menu and Parameter Display
16-character alphanumeric LED display

Frequency Response

30 Hz to 10.2 kHz
±0.1 dB
11.9 kHz
-3 dB
16 kHz
-100 dB

Audio Outputs

Audio Monitor
+10 dBm, 600Ω, balanced (XLR)
Audio Test
2.5 Vrms, unbalanced (BNC)
Frequency Response
±0.1 dB, 30 Hz to 10.2 kHz
Distortion
≤0.1% @ 99% modulation
IMD (SMPTE, CCIF and DIM)
≤0.1% @ 99% modulation
Signal to Noise Ratio
75 dB
Signal Delay
Test 3 ms, Meter 90 ms

Carrier Level

Automatic Carrier Level Adjustment Range
25-150%

Remote Meter Output

Remote Meter
Jack for optional MP-17 analog remote meter panel

Remote Alarms

Relay Functions
Loss of Modulation Normal, Negative PPM, Positive PPM, Loss of Carrier, Remote, General Alarms
Relay Configuration
Relays can be set NO or NC

Interfaces

Serial Interface
RS-232 / RS-422
Unit Interface
Wizard Standard Interface

Power Supply

Power Requirements
20 Watts, 100-240 VAC, 50/60 Hz

Packaging

Dimensions
19" W × 1 3/4" H × 14" D, EIA rack mount
Shipping Weight
10 lbs

Specifications are subject to change without prior notice.

Downloads

Datasheet

AMMA-2 product overview, features, and specifications,

View Datasheet →

Operator Manual

Complete operating instructions, setup information, controls, connections, and technical information for the AMMA-2.

View Manual →

Software & Updates

Download current AMMA-2 software and review available updates.

Software Updates →