That's not so surprising Gary !! te Way the Beverages and similar slow-wave antennas work is that they depend on the lossy GND underneath for their operation, so a salt marsh would not be a very beneficial GND structure under a Beverage!
73, Charlie, K4OTV -----Original Message----- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Gary Smith Sent: Tuesday, February 25, 2014 5:09 PM To: Topband@contesting.com Subject: Re: Topband: AM broadcast tower and 160m dxpedition My Inv-L is on a salt marsh on Long Island Sound in Connecticut & I ran two bidirectional 860' beverages over the salt marsh. I had terrible results with the beverages, very noisy and hardly any improvement over the Inv-L, much of the time the Inv-L was more effective on Rx. With that, my experience of beverages & salt marshes says to avoid this route. I ended up with a HI-Z Triangular array for Rx and it works very well at the same location. Gary KA1J > No, I don't believe 240' is too high - especially if the tower has a base > insulator! It would be so close to 1/2 wave on 160, that it could be fed > very well as a 1/2 wave radiator on 160, either via a parallel tuned tank or > a 1/4 wave of perhaps 450 oh ladder line. A 1/2 wave radiator wis an > excellent transmit antenna, and, because of the high feed-point impedance > can be driven against a very modest ground arrangement > > Like you, though, I believe they would do well to put up some terminated > loops, or perhaps a Beverage (or 3?) for receive antennas! A 240' vertical > would, I think, be a VERY noisy receive antenna. If they put up a KAZ > terminated loop that only requires one overhead support, they could steer it > around with ropes and weights on the ground. The KAZ is like ON4UN's FO0AAA > 160 receive loop. > > 73, > Charlie, K4OTV > > -----Original Message----- > From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Richard > Karlquist > Sent: Tuesday, February 25, 2014 3:38 PM > To: topband@contesting.com > Subject: Re: Topband: AM broadcast tower and 160m dxpedition > > Congratulations on your adventure. > > In the past, I have seen some of these AM tower efforts > ruined by lousy receive conditions. I suggest you > get an advance team out to the site to check > out the noise level etc. and maybe put up some > temporary beverages, loops, whatever and LISTEN > on them. Use WWV and WWVH on 2.5 MHz as a beacon. > > Others can comment on whether 240 feet is too high. > > Rick N6RK > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband > --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com _________________ Topband Reflector Archives - http://www.contesting.com/_topband _________________ Topband Reflector Archives - http://www.contesting.com/_topband