I'm glad to hear that you are using a busy frequency detector, Dave.
The detectors in PK232 and SCS modems are certainly better than
nothing, but are quite limited. Neither detects PSK31 transmissions,
for example. As part of the SCAMP project, Rick KN6KB (a member of
the Winlink team) developed a soundcard-based busy detector that was
reported here to be very effective at detecting most modes found on
the ham bands today. I have repeatedly suggested that Rick's detector
be incorporated in WinLink PMBOs -- a straightforward and inexpensive
process -- but there has inexpicably been no progress on this front
for several years.
Our HF amateur bands are a shared resource; no one can stake a claim
of ownership of any frequency or set of frequencies unless an
emergency has been declared. If contests draw more amateurs to the HF
bands -- as intended! -- then yes, there will be more congestion and
it will be harder to find a clear frequency on which to exchange
messages. Using HF amateur bands to offer a message passing service
with guaranteed quick delivery times is simply incompatible with the
defined usage model for these bands. There are techniques you could
use to optimize performance -- like QSYing to the WARC bands during
contests -- but nothing short of exclusively-assigned frequencies
would enable you to achieve a guaranteed Quality-Of-Service. I
personally don't think the assignment of exclusive frequencies to
specific sub-groups is consistent with amateur radio -- except during
a declared emergency.
73,
Dave, AA6YQ
--- In digitalradio@yahoogroups.com, David Struebel <[EMAIL PROTECTED]>
wrote:
>
>
> ----- Original Message -----
> From: David Struebel
> To: [EMAIL PROTECTED]
> Sent: Thursday, December 27, 2007 4:33 PM
> Subject: Re: [illinoisdigitalham] Will You Let FCC Kill Digital
Radio Technology?
>
>
> Hi Everyone,
>
> I've been following this debate for the past several days and
finally have to add my two cents.
>
> I'm part of NTSD, that's the National Traffic System Digital...We
mostly use the old version of Winlink (before Winlink 2000) also
reffered to as "Winlink Classic" running
> Pactor I II and sometimes III... We used to use AMTOR and Clover
but have all changed over to Pactor... Many of us are still using PK-
232MBX's for Pactor I, others are using SCS TNC's All our connects
occur in the automatic band segments... Winlink Classic has a very
good "busy detector" in it... I've seen it work on not only Pactor,
AMTOR, and Clover signals but other including RTTY, dead carriers
etc...
> Winlink classic when it hears another signal, postpones the connect
and then tries 15 minutes later for a total of three attempts at a
clear frequency.
> I can tell you that with an active busy detector, our systems are
almost helpless against RTTY signals that come into the automatic
band segments especially during contests... Traffic thru put declines
severely during these contests.
>
> We're happy with staying within the automatic band segments with
our 500 Hz Pactor I and Pactor II signals... It would be nice if
others realized that the automatic segments do contain stations
with "busy detector" armed and ready and please refrain from casual
operation there, especially during a contest.
>
> I know I'm going to get a lot of flack from those of you that don't
like automatic stations, but like I said Winlink 2000 is not the
only Pactor operation around running automatically... We prefer to
stay in the automatic band segments... Please have the common
courtesy to respect our operations.
>
> Dave WB2FTX
> Eastern Area Digital Coordinator- NTS Digital
> Section Traffic Manager- Northern NJ
>
>
> ----- Original Message -----
> From: Rick
> To: [EMAIL PROTECTED]
> Sent: Thursday, December 27, 2007 4:10 PM
> Subject: Re: [illinoisdigitalham] Will You Let FCC Kill Digital
Radio Technology?
>
>
> Packet?
>
> This does not have much to do with the subject though.
>
> John Becker, WØJAB wrote:
> > Rick you of all people should know that one of the older systems
> > had a " auto-detect " or " busy detection " that worked very
good.
> >
> >
>
>
>
>
>
>
> --------------------------------------------------------------------
----------
>
>
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12/27/2007 1:34 PM
>
