[Skimmertalk] Fwd: [SECC] FW: [MRRC] Using new filter commands to avoid busted spots

Pete Smith N4ZR n4zr at contesting.com
Thu May 31 04:26:58 PDT 2012

For what it's worth, a couple of comments on Bob's talk.  The "Unique>2" 
filter, which I told him about, requires at least 3 (not 2) Skimmers 
worldwide to hear a station before it is posted.  There is nothing 
sacred about the "2", though - you could change it to >1 or >3, 
realizing that each increment will delay your receipt of the spot a little.

Also, setting a fixed XIT amount may not be such a good idea.  Here's 
why - the DX cluster network only reports spot frequencies to the 
nearest 0.1 KHz.  The DX may actually be heard on 14020.49 or 14020.51, 
but it will be spotted in those 2 cases as 14020.4 or 14020.5, 
respectively.  If your XIT is set to +0.1 KHZ, then half the time you 
will be up to 150 Hz off zero beat.  That's a bit too much to be sure of 
being heard.

If a spot goes out on 14020.4, with today's VFOs, anyone who jumps on 
that spot is likely to be within a few Hz of the rounded frequency.  
Meanwhile, the DX may be up to 49 Hz higher or lower.  The Skimmer 
pileup is on the spot frequency, not the DX's frequency.  I know that 
these sound like small differences in frequency, but they can be important.

What I do, instead, is to tweak the VFO a little while I'm verifying the 
station's callsign, to center it a little better in my filter passband.  
That has the same effect of getting me away from the Skimmer pileup, 
plus it probably centers me better in the DX's filter.

73, Pete N4ZR
The World Contest Station Database, updated daily at www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000 and
arcluster.reversebeacon.net, port 7000

On 5/30/2012 9:48 PM, Mack McCormick wrote:
> ---------- Forwarded message ----------
> From: *Jeff Clarke*
> Date: Wednesday, May 30, 2012
> Subject: [SECC] FW: [MRRC] Using new filter commands to avoid busted spots
> To: secc at contesting.com
> Some useful information
> -----Original Message-----
> From: mrrc-bounces at contesting.com<javascript:;>  [mailto:
> mrrc-bounces at contesting.com<javascript:;>] On
> Behalf Of Kenneth Silverman
> Sent: Wednesday, May 30, 2012 5:40 PM
> To: MRRC Reflector
> Subject: [MRRC] Using new filter commands to avoid busted spots
> While K3LR usually posts the Dayton Hamvention presentations, here's N6TV's
> presentation in advance.  Lots of great info!
> Thanks to N6TV for letting me pass this along.
> 73, Kenny K2KW
> Message: 4
> Date: Tue, 29 May 2012 19:58:00 -0700
> From: "Bob Wilson, N6TV"<n6tv at arrl.net<javascript:;>>
> Subject: [NCCC] Using new filter commands to avoid busted spots
> To: NCCC Reflector<nccc at contesting.com<javascript:;>>
> Message-ID:
>        <CAOmNKGLHpPG7hxWE-RWhGyUrX9c6Vhq+OWyO=a7kaE=pzM79Sw at mail.gmail.com<javascript:;>
> Content-Type: text/plain; charset="iso-8859-1"
> I've posted the slides from the talk I gave at the Dayton Contest Forum,
> "Using the Reverse Beacon Network as a Contesting Advantage", here:
> http://bit.ly/UsingRBNPDF
> Slide 16 shows how to avoid most busted spots from the RBN.  To summarize,
> connect your cluster software or contest logger to
> arcluster.reversebeacon.net port 7000, then sign in with your callsign and
> enter the following command to establish a filter:
> set dx filter call=N6TV or (Skimmer and Unique>2 and (SpotterState=CA or
> SpotterState=NV or SpotterState=UT))
> Where you substitute [yourcallsign] with your own callsign (without the
> brackets), so that you can still see all the Skimmers that hear *you*, e.g.
> call=N6TV.
> *
> *
> New "Unique>2" filter (only available on AR Cluster V6 nodes) means that the
> spot has to be heard exactly the same way by at least *two* skimmers before
> you will see it.  This works well.  Only spots from the specified states
> will be shown.
> SpotterCqZone is also supposed to work, but at present, it doesn't seem to.
>   I've sent an email to AR Cluster author AB5K about that.  No reply yet.
> 73,
> Bob, N6TV
> _______________________________________________
> MRRC mailing list
> MRRC at contesting.com<javascript:;>
> http://lists.contesting.com/mailman/listinfo/mrrc
> _______________________________________________
> SECC mailing list
> SECC at contesting.com<javascript:;>
> http://lists.contesting.com/mailman/listinfo/secc

More information about the Skimmertalk mailing list