Good Equipment Advice Directed Toward Newcomers

      It’s noon Monday (this post was originally made back in Dec of 2009) and I’ve just updated this post with a few good links.   This post is about getting new guys to think about better antennas and coax, so they can fully take advantage of the DX potential that’s possible on V/UHF.   In short, if you want to stick with your ground plane and RG-8X, you will continue to enjoy the reliable communications that repeaters provide.    On the other hand, if you want to start working guys 200-300 miles on direct paths, using USB mode on bands like 50, 144, 222 and 432 MHz, then please read on.  

  I get new folks visiting here all the time, so let’s clear something up, before we go any farther.   All of the activity I’m talking about below uses USB mode (except for the 146.43 FM net on Thursdays).   All of the USB activity uses horizontally-polarized antennas, which is the norm with 90-95% of us DX’ers.   You can certainly get your toes wet using your existing vertical antenna, but your range will be limited because you lose 20 db of signal with cross-polarization.  
    If you really get the urge to move forward on 6m, 2m, 1.25m, 70cm … you want horizontally polarized antennas to take advantage of the true potential.    The 200, 300 mile contacts are taking place with guys who have at least medium-sized beams pointed at each other.   Those 200-300 mile Q’s occur under flat conditions.   With occasional band enhancement, you will get some contacts in the 300-800 mile range.   It’s not common, but not nearly as rare as guys think.   It also helps to have a clear horizon.   You do not need to have these antennas up 60-100′, if you have a decent horizon.   But it’s always best to have your V/UHF antennas up as high as you can safely go.  If you absolutely cannot do a yagi, then consider a horizontal loop, or stack a pair for a 3db gain.   Horizontal loops can be surprisingly effective.    They also are a great complement to a beam because you hear things with the omnis that you may not hear off the side of a yagi. 

     You will notice I talk about antennas often, and rigs very seldom.   The antennas are WAY more important on weak-signal V/UHF than the rig.   I occasionally hear from guys who want to buy the Dominator 2000 or the DX-King 8000, or whatever.   They all want to know what the right rig is.   Then they say they will use a ground plane on the rooftop.   I just smile, as I stifle an urge to laugh.   The guys who won’t do decent antennas are the guys who will lose interest in weak-signal V/UHF.   

      I’ll say this again:   Concentrate on the most antenna you can put up, if you want optimum performance.  Don’t bother spending big bucks on a rig, and then attach a 5 or 10 cent antenna to it.   You may as well stick with an H/T and a rubber duck.   Antennas, antennas, antennas.     You would be far better off putting $1000 of antennas mated to a used $200-300 rig than the other way around.   You probably won’t believe me on this, and that’s fine, it’s a free country.   I simply want you to get the maximum enjoyment out of weak-signal V/UHF.   To do this, you want to work some DX occasionally.   Or perform well in the contests.   To achieve those goals, get the best antennas you can up as high as (safely) possible.

      If you have homebrewer in you, here’s a great way to save big $$ on antennas.    Check out this link http://www.wa5vjb.com/yagi-pdf/cheapyagi.pdf
      If you can follow the detailed plans, you will end up with modest yagis that work well.    Guys I know have made these antennas and have been very pleased.   I am not a homebrewer so don’t ask me for further details.   I’m just saying that these WA5VJB Cheap Yagis are proven performers, if you can homebrew.   They would also make a great project for a club to work on over the winter.   Then come springtime, you can put ’em up and hear what you’ve been missing.  

     A final thing to consider is your coax or feedline.   To make these 200, 300 mile contacts, you want every last db you can get.   A few db may be the difference between no signal and good copy (with headphones) in the S1 range.   You don’t want to wimp out on coax.   Here are a few links that show the loss characteristics with various coaxes.   http://www.therfc.com/attenrat.htm   or try   http://www.ocarc.ca/coax.htm     I found these links by Googling “coaxial cable loss chart”.
     Some will say that it’s not worth getting concerned about a few db’s.   I’d say that any way you can improve your system by at least 1 or 1.5 db, you will notice an difference with marginal signals on weak-signal V/UHF.  You start gaining a few db’s with a better yagi, plus a few db’s with better coax, use a good preamp, quality headphones… it adds up quickly.    
     Main point is that while cheap coax may be just fine on HF, it will seriously degrade your signal on VHF/UHF, especially as you get on 144 and above.  If you’re going to the trouble of putting up good antennas, then don’t throw away your signal with cheap coax.   If you have coax runs of 70-100′, you want to be at least in the 9913 or LMR-400 range, especially above 2 meters.   If you have a run of more than 100′, then LMR-400 or perhaps even hardline is necessary.

One Response to “Good Equipment Advice Directed Toward Newcomers”

  1. Dave Says:

    3 db loss in your coax is a loss of half your radiating power.