Monday, June 11, 2012

Stealth antennas for the Amateur Radio Operator

STEALTH ANTENNAS FOR CHALLENGING SITUATIONS

In my last post, I outlined a few ideas that could get you back on the air despite restrictive covenants, HOAs, and limited space.  I've tried many of those designs myself with varying success.  Despite their shortcomings, hidden antennas can work if you're creative, run qrp, and use digital modes.  Since I enjoy SSB at times, I've had to be certain that my signals don't overload nearby stereos, tv sets, and even telephones.  Some of the newer electronics have very little filtering and are subject to overload with even moderate power levels (100 watts).  Add to this the proliferation of apartments, condominiums, and generally closer neighbors, and you get a situation where amateur operators can get blamed for everything.  I've had my share of complaints, even when I was off the air! The mere sight of an antenna can let some people's imaginations run wild.  A few years ago, I had a neighbor who complained that my Yaesu FT-7 was tearing up his television.  Considering that the Yaesu FT-7 peaks out a little under 20 watts and over-the-air television is marginal to non-existent along our coastal area, I had a real problem on my hands.  Of course, this scenario was played out before direct tv and cable fully penetrated the Hamakua Coast area of Hawaii Island.  Anyway, my neighbor found me in the garage workshop cleaning the venerable Yaesu.  When I explained that I wasn't on the air and that my feedline was disconnected, he mellowed out a bit.  The problem was finally traced to a corroded tv antenna and salt-encrusted power lines from the Hawaii Electric Light Company.  At night you could see arching along the pole insulators--quite a sight.  Salt air and rain have given the local power company fits.  Crews spend a lot of time keeping the lines clear of fallen tree limbs, corrosion, and broken insulators.  I don't fault the power company--those elements cause havoc with vehicles, metal poles of all types, and even amateur radio antennas.  That's one cost of living in a warm, maritime environment.

So, with that experience in mind, I vowed to make my station as clean as I could, run only enough power to get the job done, and conceal my modest antenna farm from peering eyes.  Armed with light gauge wire, some antenna swivels from DX Engineering, and camoflagued fiberglass  poles, I've been able to have a decent station that get a good number of contacts.  When I'm done with operations, all I do is lower the mast, disconnect feed lines, and "keep beneath the radar."  Most of my new neighbors are tolerant of my hobby, have cable or direct tv, and seem open to cooperation.  Most of my former rfi complaints are gone since I shifted to qrp power levels and disguised antennas.  This arrangement won't work for everyone, but it seems to keep me out of harm's way.

I've made a secondary hobby of researching hidden antenna designs with the object of making my radio imprint even smaller.  Today, I ran across an article in the "radiosurvivalist.com" website by Dave Hassell, Sr. (N5IW).  He believes amateur operators can return to their hobby despite the retrictions of modern life and those ever present CC&Rs and HOAs that seem to corner the housing market these days.  Dave's article is positive, upbeat, and useful.  You can find some valuable tips by visiting his web site--http://www.qsl.net/n5iw.html.  He is particularly favorable to flagpole-type antennas, attic antennas, and disguised loops.  Granted, these compromise antennas won't break a major pileup, but they will get you on the air.  When I first moved into my small rental home, the first antenna I used was an under the house 40-meter loop fed by 450-ohn balanced line.  The house sits on a 5-foot pile and pier system (for flooding and earthquake resistance), which gives me plenty of room to string a full wave loop.  Dave recommends stinging a loop under the eaves of your house or laying a dipole on a shingled or wooden roof.  I've used full wave loops for a long time and they work.  I realize that my low level loop won't perform as well as a yagi mounted on a tall tower.  But, for local statewide nets, this NVIS antenna puts out a strong signal reaching out almost 300 miles.  And for local emergency and daily rag chew nets, that's good enough for me.  My 20-meter vertical dipole and 40-meter "upper and outer" antenna (ala Lew McCoy) fill in most of the other bands.  If I need 80 meters, I have an inverted vee assembly ready to mount on a spare fiberglass mast.  I also have an emergency HF and VHF station that can be deployed from my van.

Don't be discouraged by your restricted operating situation.  Get creative, study those antenna books, and return to the air. 

Have a good day!

Aloha es 73 de KH6JRM--BK29jx15