On VHF/UHF It’s the Antennas, Antennas, Antennas.

    This article is mainly directed at newcomers to the weak-signal side of VHF/UHF.   I’m sure there are many definitions of “weak-signal” but to me it means this:   On the SSB/CW side of 6m, 2m, 222 and 432, we’re making contacts well beyond the line of sight.   All those books you read that say VHF is line of sight?   UH… they’re wrong.  Can I see Kansas City from my QTH an hour north of Milwaukee?   Nope.   I can’t even see Kansas City from the top of my tower.   🙂    Can I see Cleveland, Detroit, Indianapolis from where my yagis are?   Of course not.   Yet I work these areas any time I can find activity, even under flat band conditions, on 2 meter SSB, on or near 144.200.   How is this possible?   Using horizontally-polarized, high-gain yagi antennas is the main reason.   Statistics show we have over 700,000 licensed hams in the USA.   How many know about the DX that is possible anytime on VHF?   Not nearly enough.  This is the story we all need to spread.  
     Horizontal polarization has always been the norm on the SSB/CW side of VHF and UHF.   If you’re trying to work 2m SSB with a vertical, you may as well stay on the local repeater.   Why do I say that?  Because when your vertical antennas are cross-polarized with the other horizontal users, you suffer from a 20 db loss and you’re losing all the DX potential that we enjoy.  Eventually, you’ll get frustrated and give up.   I don’t want that to happen.  So get your station right and start enjoying the benefits. 
    Put those yagis up as high as you safely can, preferably above obstructions.   And treat yourself to a longer yagi with some serious gain.  Get in the 7, 9, 11dbd gain region, if at all possible.    On 144, if you want to be capable of 200-400 mile contacts every day, you’re going to need longer yagis up in the clear.   A 3el or 5el yagi isn’t really that long.   Start thinking about at least 9 elements, or 11 or 13.   If you really want to make a splash, stack yagis.   Ask yourself what’s holding you back from spending a little extra $ to get a lot more range.   
     If you want to try building a VHF yagi then visit this link:     http://www.wa5vjb.com/yagi-pdf/cheapyagi.pdf   Those yagis, done properly, do work.  They also make a great club project.   Build a bunch of those yagis and get your friends on the air.   Create a pocket of VHF interest right in your own area.   And when talking with your local friends, remember this tip:   Turn your yagis away from each other and point toward different areas.   You’ll still hear local signals off the back and side of the beam, but you’ll be attracting listeners in different areas, when you beam away.  Make your weak-signal VHF goal to always reach out farther.   
     If you just cannot do a yagi, then at least stack 2 or 4  horizontal loops.  Use Google to search that term.   I’m sure many options will come up.  On 144, a 2-stack of horizontal loops is very feasible and so is a 4-stack.  Every doubling of the antennas yields nearly a 3db gain, which is significant.  Use Google to find the info you need on the proper stacking distances and properly cutting the phasing lines.  Stacking horizontal loops is a great idea in conjunction with having a higher-gain yagi.  Gives you two separate receive options — omni for closer-in signals, plus good directivity to zero in on the DX.     
     Use low-loss coax to deliver every db to your rig — especially on longer runs on bands above 6m.   Google “coax loss chart” and many resources pop up.   Research those charts.   Consider a good low-noise figure receive preamp, preferably mast-mounted if you can swing it.  If you can’t hear them, you can’t work them. 

    Here’s another quick tip:  If you can only concentrate your efforts on 1 or 2 bands, the first would be 2m or 144 MHz.   A close second would be 6m.  In fact, in a lot of cases, you can get away with less antenna on 6m.  When 6m opens up with sporadic E skip, even guys with oddball antennas will get in on at least some of the action.   Sporadic Es can be that strong.   Honestly, more I think about it these days (2010-2011) there’s probably more guys on 50 MHz than 144.     6m is  the VHF band where you can work 30, 40 states in a summer.  (heck, you can do it in a weekend, if you hit the right E skip opening in a busy contest)   You can also work many states on 2m, but it’s not nearly as easy.   (Although the proliferation of digital modes is making that a lot easier, too.   Digital modes personally don’t interest me, so you’ll have to research things like JT65 and the like on your own.) 
    But then when the E skip season dies off (prime time is early-mid May thru early August), 6m gets quiet.  It doesn’t have to, but it usually does.  So you want to have 144, too, because that’s where you’ll find more day-to-day activity, any time of the year.
   
    If you’re a new visitor here, I have a post with additional 6m info from April 13th (2011):  http://kc9bqa.com/?p=4532   If you get on 6m, please learn about the band plan.  When 6 gets busy, it’s a lot more enjoyable if everyone knows what they’re doing.   This link http://www.smirk.org/opaids.html  is very educational.

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