Lloyd: I agree totally with your observations about 10 meters. It was a pleasure to work so many stations on 10 this week-end, even with a simple wire antenna, without having to deal with so much band congestion and resulting QRM. In fact, I can't remember 10 meters being as open as it was this week-end for quite a while. It will be nice if the band stays this open for the ARRL 10-meter contest which, I think, occurs on the second full week-end in December. Tom Behler: KB8TYJ ----- Original Message ----- From: "Lloyd Rasmussen" <[log in to unmask]> To: <[log in to unmask]> Sent: Monday, October 28, 2013 7:13 AM Subject: Re: 10 and 15 meters continued > If the 40 dipole is expected to work on 15 and it is full-sized, the > third harmonic resonance frequency will be somewhat higher than 15 meters, > perhaps 22 MHz or more. This is because the 468/F formula for a half-wave > dipole includes a correction for what some call the "end effect". Also, > the > 15-meter mode will have several lobes instead of the simple figure-8 > pattern > of a dipole, so some directions may fall into nulls. > > During the CQWW contest, which I operated for about 13 hours, working 40 > through 10, I worked 320 stations in 82 countries on 10, but only 55 > countries on 15. It was a matter of allocation of time during the various > openings. Ten meter phone is so much fun because a contest can spread out > over more than 700 KHz (28.3 to above 29.0), while 20 is only 200 KHz wide > and 15 only 250. This gives a lot more stations the option of calling CQ > and you have less frequencies that are 2 or 3 layers deep in QSOs. Also, > you don't hear as many of the stations in your own country on whatever > band > is the highest in frequency at a given time. This QRM factor is not such > a > big deal in CW contests. > > > > Lloyd Rasmussen, Kensington, MD > http://lras.home.sprynet.com