Batteries are required but not included with this item. Please be sure to purchase batteries for this item.
The HM-20 from Lectrosonics is a digital hybrid plug-on UHF wireless transmitter. It enables you to transmit the signal of a microphone or a line-level source wirelessly. The HM-20 overcomes inherent channel noise with its patented hybrid technology, which digitally encodes the audio. A Lectrosonics digital hybrid receiver will decode the audio, giving the user all of the benefits of conventional FM wireless systems (range, resistance to interference, etc.) without the noisy artifacts introduced by analog compandors.
Owning a Lectrosonics digital hybrid receiver isn't absolutely necessary with the HM-20. It's backward compatible with 100, 200, and IFB series receivers, as well as being compatible with analog receivers made by other manufacturers. Phantom power from its standard XLR input jack is selectable between 5, 18 and 48 volts, making the HM-20 compatible with just about any condenser or dynamic microphone. It will run on two readily available alkaline AA batteries for 4.5 hours, or up to 12 hours with lithium.
The sound quality of the HM-20 transmitter is outstanding. The power supply provides constant voltages, switching to accommodate the life-cycle of the batteries, resulting in an ultra low noise input amplifier. It features a DSP controlled limiter that can handle peaks over 30 dB. The excellent signal to noise ratio and dynamic range of the HM-20 qualify it for use in the most demanding of professional applications.
| Type of Transmitter | Plug-On |
| # Of Channels | 256 |
| Operating Frequencies | Block 20, 512.000 - 537.500 |
| Type of Input Connector | XLR Female |
| Phantom Power | Selectable 5, 18 and 48 volt phantom power plus off position for dynamic microphones |
| Frequency Response |
35 Hz to 20 kHz (+/- 1 dB) Low frequency roll-off is adjustable |
| Battery Type/Approx. Life |
Two 1.5 Volt AA lithium or rechargeable NiMH 4.5 hours (alkaline) 12 hours (lithium) 8 hours with 2500 mAh NiMH |
| Level Control | Membrane Switches |
| Antenna Type | Housing and attached microphone form the antenna |
| Display | LCD |
| Total Harmonic Distortion (THD) | 0.2% (100 Hz to 20 kHz) |
| Signal to Noise Ratio |
At Receiver Output: SmartNR Off, no limiting 103.5, with limiting 108.0 SmartNR Normal, no limiting 107.0, with limiting 111.5 SmartNR Full, no limiting 108.5, with limiting 113.0 |
| Dimensions | 4.25 x 1.62 x 1.38" (107.95 x 41.15 x 35.05 mm) |
| Weight | 6.7 oz (190 grams) without batteries |