M-72 Wireless
Microphone Transmitter

Professional Quality

Versatile/Easy to Use

High Efficiency

Companded or Non-Companded

Small Size

No External Antenna

The M-72 wireless microphone transmitter meets the highest professional standards, yet because of its unique design, it offers operational success to even the non-professional user. When used with Comtek receivers, the M-72 transmitter reproduces the microphone's quality with indistinguishable difference. The wide dynamic range of this transmitter is made possible because of its unique soft compressor system which, along with very linear modulation characteristics and low residual FM noise, gives the most natural sound possible from a wireless microphone. To add to its versatility, the M-72 transmitter is available with either a companded or non-companded audio system for use with any Comtek receiver. Also, the M-72 will phantom power all types of electret condenser microphones or operate with dynamic microphones.

The M-72 transmitter has an LED indicator to monitor RF output and battery condition, and a microphone sensitivity adjustment is provided to optimize the signal-to-noise ratio for different applications. The M-72 transmitter utilizes a body induction antenna system. Only the microphone cord extends from the transmitter package enabling the transmitter to have a more uniform radiation pattern when the unit is placed on the body or held in the hand. A slide-open battery compartment makes changing batteries fast and easy. Higher efficiency circuitry provides even longer battery life while maintaining high fidelity and maximum FCC allotted power.


Option 1: Separate microphone muting switch for quiet audio switching.

Option 7: BNC RF output with 851 micro-mini locking connector for line and mic level audio input. Comes complete with BNC whip antenna. This option is intended for battery powered remote transmitter applications.

Base Station Option: Internal modification enables the M-72 type L transmitter to be used with the BSA-72M adapter. Available with 1/8 mono-mini connector only. Compatible with the PR-72b Personal Receiver.

Type L (Standard): Non-Companded audio processing for use with the PR-72b and MR-72 receivers.

Type C: Companded audio processing for use with the MR-182, MRC-82C and MRC-82P receivers.

Microphone Connectors:

COMPATIBLE MICROPHONES (not included with M-72)

TR-50 Tram ultra-miniature microphone with hemispherical pick-up and low cord noise.

AT-830 Audio Technica professional omni-directional electret condenser microphone.

SM-183 Shure omni-directional electret condenser microphone.

SM-185 Shure cardioid electret condenser microphone.

AT-35 Audio Technica general purpose omni-directional electret condenser microphone.

PSC-MM Professional Sound Corporation ultra-miniature, omnidirectional microphone.

HW-10 Shure head-worn uni-directional dynamic microphone for noisy environment use.

PSC-HM PSC head-worn uni-directional electret microphone for aerobic and hard-hat applications.


Audio Input: Low impedance (150-600 ohms) with external control to adjust sensitivity for -60 to -40 dBm input level. Also, will self-power electret condenser microphone.

Controls and Indicators: Microphone level input sensitivity control, and LED for RF output and battery condition indicator.

Modulation Limiter: Soft compressor type with high linear overload protection, attack time less than 1 ms, recovery time 10ms

Frequency Modulation: Up to 30 kHz deviation.

Residual FM Noise: Less than 20 Hz (30 kHz BW)

Frequency Stability: .005% crystal controlled

Operating Radio Frequency: Single channel, 60 to 216 MHz

Harmonic & Spurious Emissions: -45 dB below carrier

RF Power Output: 8000 V/m R 30 m (72 to 76 MHz) 50 mW at output port (174 to 216 MHz)

Antenna: Body induction type (no external antenna)

Current Drain:
15 mA 72 - 76 MHz
20 mA 174 - 216 MHz

Battery: 9 volt alkaline Eveready 522 or equivalent for up to 30 hours or optional 9 volt nickel-cadmium rechargable battery for five hours of operation.

Dimensions: 1 1/16 2 1/4 3 1/4 (27 mm 57 mm 83 mm)

Weight: 4 ounces (110 grams)

For more information on the M-72 Wireless Microphone Transmitter or COMTEK's comprehensive line of high quality wireless sound products, e-mail us or give us a call at (801) 466-3463. Our applications engineers will be happy to work with you!

357 West 2700 South / Salt Lake City, Utah 84115

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