The issue is not the protocol, but rather automatic operation without a busy
frequency detector. An operator invokes a remote automatic station, whose
subsequent transmissions QRM an ongoing QSO that the operator doesn't hear (but
would hear clearly if he or she were monitoring the remote station's receiver).
Participants in the ongoing QSO have no way convey "QRL" to the automatic
station.
73,
Dave, AA6YQ
-----Original Message-----
From: [email protected] [mailto:[email protected]]on
Behalf Of John B. Stephensen
Sent: Monday, February 22, 2010 3:47 PM
To: [email protected]
Subject: Re: [digitalradio] Winlink and Regulation by Bandwidth
Pactor was FSK with a 100% duty cycle (or peak to average power ratio - PAPR),
but Pactor-III is OFDM which has a PAPR similar to SSB and much less than SSB
with RF clipping so I don't see how its any worse than digital voice or SSTV.
Were the two stations in the automated segments fighting or just transferring
data in both directions? I just don't see the threat from automated Pactor
stations as they are legal on every amateur frequency outside the U.S. and they
haven't taken over there.
73,
John
KD6OZH
----- Original Message -----
From: KH6TY
To: [email protected]
Sent: Monday, February 22, 2010 00:04 UTC
Subject: Re: [digitalradio] A closer look at ROS]]
John,
The principle of regulation by bandwidth that was fostered by Winlink through
the ARRL was that any mode would be allowed in a particular segment of
bandwidths as long as the bandwidth was the same or similar. No restriction on
content or operating methods.This would have meant that the messaging stations
would have full access to all of the phone bands with no restrictions. For
example, Pactor-III which has about 100% duty cycle (modulation), compared to
30% average for uncompressed phone, could easily displace any phone QSO and the
phone operator would not even be able to identify the interfering station
because he would not be operating Pactor-III. The result would have been
dominance by messaging systems with no place left to have phone QSO's without
the possiblity of being interfered with by an automatic messaging station.
Messaging stations are run with ARQ so they fear competition of their own kind
and you can often see two automatic stations battling automatically for a
frequency. As a result they want to spread out over the band as much as
possible to avoid interference from each other instead of sharing frequencies
on a first-come-first-served basis like everyone else.
