Lectrosonics HMa UHF Plug-On Transmitter

The Lectrosonics HMa UHF plug-on transmitter turns any microphone or line-level source with an XLR connector into a Digital Hybrid Wireless channel.

Phantom power switches between 5, 15, and 48 volts, or off for dynamic mics and line sources. Output power is 50 or 100 mW, and the housing and the attached mic or cable form the antenna, so there is no separate whip.

Frequency Bands

Trew Audio carries three versions: A1 (470.100 to 537.575 MHz), B1 (537.600 to 607.950 MHz), and 941 (941.525 to 959.825 MHz, in three segments). A1 and B1 tune in 100 or 25 kHz steps across up to 76 MHz, for up to 3072 frequencies, and the 941 band offers 695 frequencies over 19 MHz in 25 kHz steps.

Audio

An ultra-low-noise input amplifier feeds a dual envelope limiter with more than 30 dB of headroom above full modulation. A 24-bit converter digitizes the audio, and Digital Hybrid Wireless sends it over an analog FM link with no compandor, for a response of 35 Hz to 20 kHz. Nu Hybrid mode gives full quality, and compatibility modes work with Lectrosonics Mode 3 and IFB receivers.

Power and Setup

Two AA batteries run it for about 5 hours with a dynamic mic, or about 3.5 hours while supplying 48 V phantom power. A multi-color LED shows battery status, the IR port copies settings from an IR-enabled receiver, and the USB port takes firmware updates.

Good to Know

Sweat and other moisture damage the HMa, so keep it wrapped or fitted with the optional HMCVR cover.

Features

Plugs into any XLR mic or line-level source
Selectable 5, 15, or 48 V phantom power, or off
Up to 76 MHz tuning range in 100 or 25 kHz steps
Selectable 50 or 100 mW output
Adjustable low-frequency roll-off
Nu Hybrid mode with Mode 3 and IFB compatibility
Runs on two AA batteries
USB port for firmware updates
IR port for fast setup
Solid machined aluminum housing

What's Included

2 × AA alkaline batteries
HM pouch (PHTRAN3)
Quickstart Guide

Specifications

Transmitter
Operating Frequencies	Band A1: 470.100 to 537.575 MHz Band B1: 537.600 to 607.950 MHz 941: 941.525 to 951.975, 952.875 to 956.225, and 956.475 to 959.825 MHz
Frequency Selection Steps	Selectable, 100 or 25 kHz
RF Power Output	Selectable, 50 or 100 mW
Compatibility Modes	Nu Hybrid, Mode 3, IFB (941: Nu Hybrid, IFB)
Pilot Tone	25 to 32 kHz, 5 kHz deviation (Digital Hybrid mode)
Frequency Stability	±0.002%
Equivalent Input Noise	−125 dBV, A-weighted
Input Level	Nominal 2 mV to 300 mV before limiting Greater than 1 V with limiting
Input Impedance	1 k ohm
Input Limiter	Dual envelope soft limiter, greater than 30 dB range
Gain Control Range	55 dB
Audio Input	Standard 3-pin XLR (female)
Phantom Power	5 V at 18 mA max, 15 V at 15 mA max, 48 V at 4 mA max, or off
Audio (Overall System)
Frequency Response	35 Hz to 20 kHz, ±1 dB
Low-Frequency Roll-Off	−3 dB at 30, 50, 70, 100, 120, or 150 Hz
THD	0.2% typical, 100 Hz to 20 kHz
SNR at Receiver Output	SmartNR Off: 103.5 dB, 108.0 dB with limiting SmartNR Normal: 107.0 dB, 111.5 dB with limiting SmartNR Full: 108.5 dB, 113.0 dB with limiting
Input Dynamic Range	125 dB with full transmitter limiting
Power and Physical
Battery	2 × 1.5 V AA alkaline
Battery Life	About 5 h without phantom power (dynamic mic) About 3 h 30 min with 48 V phantom power
Operating Temperature	−20 to 50 °C (−5 to 122 °F)
Weight	190 g (6.7 oz) without batteries
Dimensions	107.95 × 41.15 × 35.05 mm 4.25 × 1.62 × 1.38 in
Latest Specifications	Specifications are subject to change without prior notice. For current information, visit lectrosonics.com.