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Re: [IRCA] [ultralightdx] Oregon Cliff (Rockwork 4) Ultralight DU's for 7-17...Wild!

--- Begin Message --- I am a firm believer in "both kinds of DX": live and after-the-fact capture analysis.
Whenever possible you should use a mix of the old-school and new-school methods. 

Advantages of live DXing:
* You can use webstream, remote-receiver, and shortwave parallels.
* You can use high-Q tuned antennas rather than broadband. In two situations this is the way to go. One would be when you have very weak signal conditions and not enough space for a broadband antenna of sufficient sensitivity. The other would be when you are in an urban situation where any broadband antenna of sufficient gain to hear DX is going to present locals at such high levels that the receiver will create spurious signals. * You can use a phasing unit to target the specific "pest" affecting the frequency on which you're actively DXing at the time. It takes a very good antenna system (e.g. physically-large array) to deliver much better than a 25 dB null in a broadband sense. But narrow bandwidth nulls of better than 40 dB are easily had with a Quantum Phaser (or similar) and a pair of different-pick-up antennas (e.g. loop vs. whip, loops at right angle), or with two similar-pick-up antennas spaced at least 50m / 164 ft. apart. 

Advantage of after-the-fact capture analysis (Perseus, Excalibur, etc.)
* During a "hot" opening, a single top-of-hour capture gets you a whole medium-wave band worth of ID's. This would take much more time to accomplish with live DX sessions. Optimum conditions may have gone away by the time you're even halfway through the band doing it live. At US/Canada East Coast beach sites around local sunset, two top-of-hour captures (+/- 3 min.) can get you an amazing amount of choice DX. Same is true for West Coast around local dawn. And, if it's auroral, admittedly a fairly rare occurrence in recent years, you'll be busy all night on tops-of-hour as well as on the half-hours for the Venezuelans. * You can repeatedly replay a given target, trying AM, synchro AM, USB, and LSB modes; various IF bandwidths; notch filters et al. On live DXing you have less time to figure out the optimum receiver settings.
Since you typically won't have webstreams and shortwave to assist you on after-the-fact analysis of medium wave capture files, use the periods BETWEEN the tops-of-hour (:00+/-3) and bottoms-of-hour (:30+/-2) captures to do live DX, making sure to avail yourself of things that are only feasible when DXing the old-school way. You can still have TotalRecorder (or your other favorite audio recording tool) running during the live DX activity since you won't want proof of a breathtakingly rare catch passing you by. What you find out during the between-captures live DX will feed into antenna-aiming etc. decisions you may want to make before the next capture session.
When I'm in the car at the seashore, I usually start with the roof-top cardioid-pattern antenna nulling towards NYC (255 deg.) but I may later take a crack at things with the antenna null aimed 345 deg. to take Boston and Montreal down instead. Or I'll re-position somewhere between those two bearings to affect maximum reduction of the Lakes area (Buffalo / Toronto / Cleveland / Detroit / Chicago) instead. The between-captures live listening is often the thing that dictates what the most productive nulling / antenna-aiming strategy will be. 

Mark Connelly, WA1ION
South Yarmouth, MA

<<
Great loggings Gary! Sure looks like there's something 'special' about the Rockworks 4 location. And it appears it'll take one heckuva wideband set-up to 
match what you're able to accomplish with the single-frequency, hi-Q
FSL/Ultralite solution.
You may well have found a very compelling situation where LIVE, single-frequency 
listening is still 'the only way to go!'
I'm holding out hope for Chuck finding something that's close to what you're able to hear with a wideband set-up. Many of us have kinda gotten used to having huge WAV files to pore over at our leisure instead of having to either stay up all night or be truly AWAKE at sunrise to take full advantage of 
openings.

(Bill Whitacre)

--- End Message ---
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