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The Audimax 362HD features dual MPX outputs with independent level adjustments.
This allows connecting a backup transmitter or dedicating it to a nighttime transmitter. 362 Rear Mpx Pn
  • Output connectors are BNC type.
  • For MPX connection, use 75 Ohm coaxial cable (CCTV standard).
  • Cable length should not exceed 25 meters.
Proper ground distribution is essential.
When connecting to the transmitter’s MPX input, ensure the transmitter’s internal pre-emphasis network is disabled (flat response 20 - 100 kHz). Pre-emphasis in the Audimax 362HD is factory-set, available in either 50 µs or 75 µs.

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Adjusting to 100% Modulation

Modulation is adjusted by varying the equipment’s MPX output level.
It is recommended to use program material with voice and strong music (e.g., contemporary pop).
1

Prepare the input signal

  • Ensure you are using the appropriate inputs (BAL/UNBAL) according to your console.
  • Adjust the console’s audio level to reach 0 VU on peaks.
  • This way, the AGC stage works at its equilibrium point.
2

Configure processor and transmitter

  • Set all processor controls to their center position.
  • If the transmitter has modulation level control, set it to maximum.
3

Adjust MPX output

  • Adjust the 362HD’s MPX output level until reaching 75 kHz deviation (100%), measured with an FM modulation monitor or the transmitter’s indicator instrument.
Some countries allow infrequent peaks up to 110% modulation (e.g., FCC regulations in USA).
Needle-type modulation indicators may show peaks above 100% due to ballistic overshoots or average readings of sinusoidal signals. This does not indicate actual over-modulation in the system.
Once modulation level is set, proceed to customize the station’s sound by adjusting the Audimax 362HD controls.
This process does not affect the modulation level, as the processor delivers constant peak level.