Sennheiser HD400 manual HMEC 305-C NoiseGard headset, HMEC 306 NoiseGard headset

HMEC 305-C NoiseGard™ headset

The HMEC 305-C differs from the HMEC 300 in the following features:

•No Mono/Stereo switch

•Connection of headphones and microphone via XLR-5 plug

HMEC 306 NoiseGard™ headset

The HMEC 306 differs from the HMEC 300 in the following features:

•Connection of headphones, microphone and NoiseGard™ electronics to the on-board power supply system (12–35V DC) via 6-pin Redel plug

HMEC 322 NoiseGard™ headset

The HMEC 322 differs from the HMEC 300 in the following features:

•No Mono/Stereo switch

•Coiled cable

•Connection of headphones and microphone via U-174/U jack plug to a high impedance interface in the helicopter

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