Page 2 - Contents; Safety tips
112 Contents Safety tips .................................................................................................... 113 Headset features .............................................................................................. 114 Product variants ........................................
Page 3 - Set the volume to safe levels
113 The HMEC 300, HMEC 302, HMEC 305,HMEC 305-C, HMEC 306, HMEC 322, HMEC 400and HMDC 322 are pilot headsets with closed ear protector headphones and NoiseGard™active noise compensation for use in helicopters, propeller and turboprop aircraft. Safety tips • With the NoiseGard™ active noise compensat...
Page 4 - Headset features; HMEC 300 NoiseGardTM headset
114 Headset features HMEC 300 NoiseGard™ headset • New active headset with effective attenuation of external noise across the entirefrequency spectrum due to NoiseGard™ active noise compensation • NoiseGard™ active noise compensation provides clear communications even in thenoisiest environment • Ex...
Page 5 - Fail safe operation in case of power failure; Product variants; HMEC 302 NoiseGardTM headset
115 • Power supply for NoiseGard™ is provided via on-board power supply system,cigarette lighter socket or battery pack • Fail safe operation in case of power failure • Supply voltage for the NoiseGard™ system is processed by the in-line electronics inthe connecting cable • Made in Germany, two-year...
Page 8 - Delivery includes; Headset
118 Delivery includes HMEC 300, HMEC 305-C, HMEC 322, HMEC 400 and HMDC 322 headsets • Headset • 3-pin XLR socket for aircraft panel mounting (power supply via the on-board system) • Padded carry and storage bag with shoulder strap for headset and accessories • Wind screen for microphone (except HMD...
Page 9 - Recommended accessories; Replaceable gel ear cushions
119 ACX-1 ACX-2 ACX-11 ACX-22 Recommended accessories Replaceable gel ear cushions (Cat. No. 83140) BP-03 battery pack (except for HMEC 302, HMEC 305 and HMEC 306) Battery pack with XLR-3 socket for powering the NoiseGard™ electronics of the HMEC 300,HMEC 305-C, HMEC 322, HMEC 400 and HMDC 322 heads...
Page 10 - Connecting the headsets; Connecting cables for headsets; electronics
120 Connecting the headsets Connecting cables for headsets HMEC 300 and HMEC 400 headsets: 1 1 / 4 ” (6.35 mm) stereo jack plug for connecting the headphones 1 PJ-068 jack plug for connecting the microphone1 XLR-3 plug for connecting the power supply for the NoiseGard™ electronics HMEC 302 headset: ...
Page 12 - Powering options
122 Powering options There are three options for powering the NoiseGard™ active noise compensation: 1. Connection to the on-board system (12–35 V DC) 2. Connection to the BP-03 battery pack(accessory, except for HMEC 302, HMEC 305 and HMEC 306) 3. Connection to the cigarette ligther socket (12–35 V ...
Page 13 - Connecting the headset to the on-board system; Connect the
123 1. Connecting the headset to the on-board system The NoiseGard™ electronics can be connected to on-board power supply systems withoperating voltages between 12–35 V DC. The HMEC 300, HMEC 305-C, HMEC 322, HMEC 400 and HMDC 322 headsets aresupplied with an XLR-3 socket for panel mounting in the a...
Page 15 - Connecting the headset to the battery pack; Inserting / replacing the the batteries
125 2. Connecting the headset to the battery pack (except HMEC 302, HMEC 305 and HMEC 306) The NoiseGard™ electronics of the HMEC 300, HMEC 305-C, HMEC 322, HMEC 400 andHMDC 322 headsets can also be powered via the BP-03 battery pack ( ‘Recommended accessories’). The battery pack can be operated eit...
Page 17 - Connecting the headset via a cigarette lighter adapter cable; headsets
127 ACX-1 ACX-2 ACX-11 ACX-22 3. Connecting the headset via a cigarette lighter adapter cable (except HMEC 302, HMEC 305 and HMEC 306) Sennheiser offers special adapter cables with XLR-3 socket for connecting the NoiseGard™electronics of the HMEC 300, HMEC 305-C, HMEC 322, HMEC 400 and HMDC 322 head...
Page 18 - Preparing the headsets for use; Adjusting the headband
128 Preparing the headsets for use Adjusting the headband For good noise attenuation and best possible comfort, the headband has to be adjustedto properly fit your head: 씰 Wear the headset so that the headband runs over the top of your head. 씰 Adjust the length of the headband so that • your ears ar...
Page 19 - Positioning the microphone; Relocating the microphone boom
129 Positioning the microphone Relocating the microphone boom The microphone boom can be worn on either side of the mouth. 씰 Loosen the quick-fixing device. 씰 Rotate the microphone boom by 180 ° . 씰 Tighten the quick-fixing device. Positioning the microphone towards the corner of the mouth The HMEC ...
Page 22 - Using the headsets; Turning NoiseGardTM; When using the BP-03 battery pack, set the NoiseGardTM ON/OFF switch; Adjusting the volume; Exposure to loud sounds can cause hearing damage!; Set the volume control
132 Using the headsets Turning NoiseGard™ on/off With the NoiseGard™ active noise compensation turned off, the headset can be used asa conventional headset.Turn on the NoiseGard™ active noise compensation by setting the ON/OFF switch to ON. When using the BP-03 battery pack, set the NoiseGard™ ON/OF...
Page 23 - Mic Gain Adjustment; Adjusting the microphone gain
133 Mic Gain Adjustment Adjusting the microphone gain According to JTSO approval C58a, the microphone output voltage has to be factory-preset to 400 mV. If this output voltage is too high or too low for your intercom system,it can easily be re-adjusted on the microphone. To do so, use a small slotte...
Page 24 - Spare parts; Wind screen for MKE 45-1 electret microphone; Replacing the wind screen
134 Spare parts The following spare parts are available from your Sennheiser agent: • Wind screen for MKE 45-1 electret microphone • Ear cushions • Headband padding • Cable clip • Carry and storage bag with shoulder strap Replacing the wind screen If the wind screen for the electret microphone shows...
Page 25 - Replacing the headband padding; Replace the headband padding if it is damaged.
135 Replacing the headband padding Replace the headband padding if it is damaged. 씰 Pull the Ziploc type fastening strips of the headband padding apart and remove theworn headband padding. 씰 Put the new headband padding around the headband. 씰 Pull the two edges of the headband padding together so th...
Page 26 - In case of difficulty; Problem
136 In case of difficulty If problems occur that are not listed in the below table, please contact your Sennheiseragent. Problem Clear communication but noactive noise compensation Possible cause and what to do The NoiseGard™ electronics are turned off. 씰 Check to see if the ON/OFF switch is set to ...
Page 28 - Valuable information on NoiseGardTM; The NoiseGardTM principle
138 Valuable information on NoiseGard™ The NoiseGard™ principle One of the greatest stress factors today is noise. Research has shown that noise affectsthe nervous system, and can cause tiredness, poor concentration, irritability and tension.Of even greater concern is the permanent damage to hearing...
Page 31 - Connector assignment
141 2 3 1 4 2 1 3 solder side 5 3 1 2 ; ; 1 2 ;;;;;;;;;;;;; ;;;;;;;;;;;;; 3 4 6 Connector assignment U174/U jack plug 1 Microphone Lo2 Audio Hi3 Microphone Hi4 Audio Lo HMEC 300 1 Not assigned!2 Microphone Hi3 Microphone Lo 1 / 4 ” (6.35 mm) stereo jack plug 1 Audio Hi left2 Audio Hi right3 Audio Lo...
Page 32 - Technical data; Headphones
142 Technical data HMEC 300 HMEC 302 HMEC 306 HMEC 400 Headphones Transducer principle dynamic Ear coupling circumaural, closed Frequency response 45–15,000 Hz Nominal impedance active/passive 300/150 Ω , mono 600/300 Ω , stereo Attenuation (active and passive) > 25 – 40 dB Max. sound pressure le...
Page 33 - General data
143 HMEC 300 HMEC 302 HMEC 306 HMEC 400 General data Connecting cable 1.5 m, unilateral Weight without cable 370 g Power supply for NoiseGard™ 12–35 V DC Current consumption 27 mA (zero signal current), max. 80 mA Fuse 500 mA thermo fuse Connectors 6.35 mm stereo jack plug 6.35 mm stereo jack plug 6...
Page 36 - Certificate of Conformity
146 Certificate of Conformity Sennheiser electronic GmbH & Co. KG declare that this device conforms to the applicable CE standards and regulations. For up-to-date information on Sennheiser products, you can also visit the Sennheiser Web site at “http://www.sennheiser.com”.