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What Helmet Are You Using / Recommend?

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Caveat emptor !!!


When buying a used or refurbed helmet, make sure you're getting the right avionics for 'em. Military helmets come with 17 Ohm earphones, a non-amplified dynamic mic and a 3 foot straight cord.


99.999999999999999999999% of civil comms use the David Clark de facto standard of 300 Ohm earphones and either amplified dynamic or electret mics.


The problem with mismatched comms are the following:


Earphones: Imagine you have 17 Ohm earphones, while all your pax are wearing DC headsets w/300Ohm earphones. Seeing as your earphones have less impedance, you will draw almost all the ICS current. The result is you'll hear everything too loud and your pax very little or not at all. :down:


Mic: This is a common problem on any a/c with VOX (voice triggered) ICS. If you have a non-amplified dynamic Mic, the slightest whisper (or cabin noise, so don't fart) on your part will trigger the ICS, so you have to set the squelch very high. The result is your pax will either have to scream or use the foot switch (if so equipped) to talk on the ICS. I've seen the problem manifest itself with two electret mics of different brands. It's a royal pain in the arse... :down:


Oh yeah, try longlining with a Bell with a 3 ft cord. Better yet, try plugging into an Astar with a 3 ft cord !!! :wacko:

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