Topband: Stew Perry : FO8RZ

Victor A. Kean, Jr. vkean at k1lt.com
Mon Dec 28 20:08:48 PST 2009


On Sunday 27 December 2009 10:25:54 pm f5phw at free.fr wrote:
> Very happy to be heard by K1LT in OH (559). 

and from: [CQ-Contest] Using spectrum scopes in contests
> Anybody seriously making use of spectrum scopes in contests? If yes, how do
> you use them?

I have to reply to these messages together, since they are related.

Many of you are bored by my numerous soapbox comments about my phased array and
software defined radio "receiving system" (its an antenna *and* a radio at the
same time).  One of the benefits of this system is the constantly available spectrum
display.  I've hacked some software together so that I can use the SDR as the
receiver and my IC765 as the transmitter with the transmitter tracking the receiver.
(It hacking because the 765 is connected to a different computer and nominally 
being controlled by WriteLog.)

So, if I see an interesting signal on the SDR screen, a single mouse click puts that
signal in the center of the receiver passband and also puts the transmitter on the
same frequency.

On the spectrum display, weak signals are thin and dim, while strong signals are
fat (usually quite fat from the key clicks) and bright.  When its time to S&P,
rather than crawl across the entire band verifying that each fat line is someone
I've worked before, I just click on all the dim lines because they are frequently
interesting.  Furthermore, on 160 the interesting signals often congregate in the
1830-1835 region.

So, while working my way up the band during an S&P session, I noticed an interesting
signal off by itself around 1835.  That turned out to be VE1ZZ working ZL3IX.  I had
the phased array pointed at 270 degrees for W6s and 7s, but I turned it to 240 to see
if I could hear ZL3IX.  (Its that sharp.)  I did and I worked him.  When I turned the
antenna, another even dimmer line appeared a couple of kHz lower.  I clicked on that
line and heard FO8RZ sign and then promptly fade into the noise.  I couldn't tell if
he was working the contest from just that one call.

Nevertheless, while chasing other dim lines around the screen, I kept an eye on 1832
(actually, the whole "window").  A couple of times the faint line reappeared and I 
clicked to see what I could hear.  The last time I did so, I heard FO8RZ CQ, so I 
called and completed a QSO.  I never saw anyone else call him.

I wish I had recorded that QSO, because I could then play it back exactly as I heard
it, since its digital, and the recording captures the spatial content which means I
can steer the "antenna" (or am I steering the radio?) during the playback and also
tweak the filters and go see who was causing the key clicks, etc.  Note that all I
had to do was click a single 200x200 pixel "button" to start a recording that
pre-dates the click by 10 seconds (because the recording program is constantly
buffering the data from the SDR hardware).  But I didn't even think of it.  I 
suppose I could record the entire contest, but at 3 megabytes a second, each 24 hour
recording would require 259 gigabytes.  Maybe I'll go buy a terabyte hard drive for
the CQ 160.

Anyway, I ramble.

Victor, K1LT


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