A Definition of “Weak-Signal” V/UHF

   8am Wed.

   Recently on the SMC  email reflector (Society of Midwest Contesters — see www.w9smc.com) there was a discussion about how we define “weak-signal” V/UHF. 
   N0AX Ward distilled those comments into something he recently posted to the ARRL Contest Update email, which was dated July 17, 2013.  With N0AX’s permission, I am re-posting his definition here:
  
  “Weak signal — referring to CW/SSB on the VHF+ bands, the word “weak” doesn’t necessarily mean that the received signal is weak. (kc9bqa adds: or that the transmitted power is necessarily QRP, either)   It refers instead (roughly) to the ability of a mode to achieve a useful signal-to-noise ratio in a given bandwidth.  Stated more simply, CW and SSB “do better” when signal levels are low because their power is concentrated in a narrower bandwidth than FM.  This enable contact over longer distances via CW and SSB, all other things like transmitter power and antenna gain being equal.  The tradeoff is that FM has better noise-immunity, which is more important for regional (or local) communications.”
   That’s the concise part of this post. 

   KC9BQA adds — The more I think about it, the more I wish there were some other term (rather than weak-signal) we could use.  “Weak-signal” just has a negative connotation to it.   Plus, when we’re enjoying the SSB/CW/digi side of V/UHF, we’re working stations 100, 200, 300, sometimes 800 or 1000+ miles away.   We’re the ones enjoying the DX, which to me is “strong”.  
   
 To dispel any remaining myths, Joe Q. Ham needs to know this: 
    1)  Weak-signal V/UHF refers to SSB/CW/digital ops on portions of 50, 144, 222 and 432 MHz.   There are also microwave bands like 902, 1296, 2304, 3456 MHz, plus 5, 10 GHz and on up into laser.   The vast majority of VHF’ers have at least 50 and 144 MHz, with 432 MHz close behind.  
    2)  Weak-signal V/UHF ops achieve superior range (well beyond line-of-sight) using horizontally-polarized antennas with higher gain.  Typical range for a station with 50-100 watts out + 8-12′ long yagis with a clear horizon is 200-300 miles, with flat band conditions on 50 thru 432 MHz.    Occasional band enhancements can produce DX up to 1000+ miles away.   For better range, improve and raise antennas, improve coax, add mast-mounted preamps and consider increasing output power.  
    3)  It also helps to turn down your squelch and use headphones when digging into the noise for light-copy stations.  This is one instance where the term “weak-signal” applies.  We often hear and work stations that are well into the noise with a combination of patience and persistence.   These are signals anyone with an FM-only background would never know existed. 
    4)  If you are a ham with some DX’er in you, give “weak-signal” V/UHF a try.  Step outside the narrow-minded box that says V/UHF is all about local or line-of-sight communications.  Don’t always believe what “The Book” says.   Get horizontally-polarized, get higher-gain antennas, get or borrow an all-mode rig and start working DX on V/UHF bands like 50, 144, 222 and 432 MHz.

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