The problem is that only a few of the VHF channels are full
duplex. Most are half-duplex (what you call simplex, but that's
not accurate -- simplex is one way only, like AM and FM broadcast
radio).

--
Chuck Tribolet

http://www.almaden.ibm.com/cs/people/triblet

Silicon Valley: STILL the best day job in the world.


"Peter" wrote in message ...

"Vito" wrote in message
...
NavNut wrote:

I'm confused. Is there a way to do truly "hands free" communications
around
a boat, or are those "hands free" headsets a bit of misnomer -- i.e. you
have to push a button to talk?

Yes (see other answers) it's called "VOX" (Voice Operated Transmit) not
"full duplex" but it's oft more PIA than not. Noise triggers it and you
can't hear while transmitting. True "full duplex" overcomes this by
using one frequency for transmit and another for recieve. It's
considered only a tad more discourtious than shouting.

73, Howard

I thought there was either Simplex or Duplex.
At least that's how they described the hands free car kits a few years back.