About 4:1 ratio should work. Most folks like to roll their own but you can also try: http://www.minicircuits.com/products/Transformers.shtml Should work if you're not near any high RF fields Regards, Mark Durenberger -------------------------------------------------- From: "Les Rayburn" <les@xxxxxxxxxxxxxxxx> Sent: Monday, January 02, 2012 6:39 PM To: "Mark Durenberger" <Mark4@xxxxxxxxxxxxxxx>Cc: "DX @NRC" <am@xxxxxxxxxxx>; "Mailing list for the International Radio Club of America" <irca@xxxxxxxxxxxxxxxx>
Subject: Re: [NRC-AM] [IRCA] Building a "state of the art" MW DX station
Mark, Excellent points regarding the change in "mindset" when using a SDR receiver. Hadn't really thought it about it that way. I might be able to erect a "fold over" vertical antenna that I could deploy only during listening sessions. Assuming something like 30 feet in length, what would I need for a matching transformer? Les Rayburn, Director High Noon Film 130 1st Avenue West Alabaster, AL 35007-8536 (205) 621-7500 (205) 621-7505 FAX (205) 253-4867 CELL http://www.highnoonfilm.com On 1/2/2012 6:23 PM, Mark Durenberger wrote:Hi Les...good for you! As a general comment addressing two of your questions: The "real" SDR is a tool you'll fall in love with. However...you'll have to make somewhat of a tradeoff from the original way of thinking. We've all used loops to pinpoint and tune a specific frequency. That's sort of counter-productive when you're using an SDR to capture the entire band because you usually don't want to favor a unique channel. So if you're doing wideband with SDR you're probably going to want to do a Beverage or a vertical. Sounds like a Beverage is out for you. I've had tremendous luck with a 30-foot vertical and a Perseus SDR. No amplification needed; just a matching transformer. It also sounds like you expect a lot of local noise. So you'll probably want to look at a real noise-cancelling antenna. Google Dallas Lankford's vertical antennas and some of Mark Connelly's work. Regards, Mark Durenberger -------------------------------------------------- From: "Les Rayburn" <les@xxxxxxxxxxxxxxxx> Sent: Monday, January 02, 2012 6:02 PM To: <am@xxxxxxxxxxx>; <irca@xxxxxxxxxxxxxxxx>; <Tvfmdx@xxxxxxxxxxxxxxxx> Subject: [IRCA] Building a "state of the art" MW DX stationiAfter an absence from medium wave dxing due to a move to a new deed-restricted QTH, I find myself itching to get serious again. While my present home is far from idea (HOA, and high local noise levels), I'm determined to make the best of it. Presently, I have the following equipment available for us: Icom 746 Pro transceiver RF Space SDR-IQ receiver Wellbrook AL-1530 Loop antenna Radio Plus Quantum Phaser LF Engineering M-601C Active Whip antenna LF Engineering H-800 Active Whip antenna LF Engineering N-300 Group loop isolator My questions are numerous, but here are the general ones: 1.) To build a state of the art system, would you recommend up-grading the SDR-IQ to the Perseus or new WinRadio SDR? 2.) Are there active whip antennas that perform better than the LF Engineering models? (I have mounted these to my roof vents, painted them black--and so far, no complaints from the neighbors. 3.) I have a undeveloped drainage ditch next to my home that offers the possibility of a beverage on the ground antenna that would run N/S for 500-800 feet. What couplers would you recommend for this use? 4.) Anyone tried the LF Engineering M-607 Active Loop antenna? Pricey at $390 but perhaps worth it? 5.) Any other station accessories that would improve things for me? Primary interest is in domestic MW DXing, though I don't mind logging TA signals when they "in" (rare here). Love to DX stations in the Western part of the country most of all. Thanks for the advice, and 73, Les Rayburn, N1LF Alabaster, AL (Near Birmingham) -- Les Rayburn, Director High Noon Film 130 1st Avenue West Alabaster, AL 35007-8536 (205) 621-7500 (205) 621-7505 FAX (205) 253-4867 CELL http://www.highnoonfilm.com _______________________________________________ IRCA mailing list IRCA@xxxxxxxxxxxxxxxx http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@xxxxxxxxxxxxxxxx_______________________________________________ The NRC AM mailing list Now accepting pre-orders for the 32nd AM Radio Log Questions? owner@xxxxxxxxxxx Latest DX Tests are found at http://www.nrcdxas.org
_______________________________________________ IRCA mailing list IRCA@xxxxxxxxxxxxxxxx http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@xxxxxxxxxxxxxxxx