indoor2.art

一个很小和天线计算程序

SUBJECT: Indoor Antennas for HF & VHF/UHF

       I thought I would conclude the HF foil antenna here and move on to
another subject.  Connections from the foil to the coax or BALUN are via 
the copper tape.  There are copper tapes available on the market that are
used for EMI applications.  These tapes are expensive so if you can get
a piece of some of that tape from a buddy, it will work wonders for you.

       Otherwise, there is a trick with regular copper tape and the aluminum
foil that you can do.  It's a simple folding technique that insures a good
connection and yet requires no soldering except for the coax / BALUN
connection.

         ===========================================  Aluminum foil
              |-----------------------------------||
              | ====================================
              |------------------------------------------- Copper tape


       This folding method insures good contact on more than one surface.
One warning, do not leave air gaps as it will have a capacitive effect.

       Solder doesn't stick to Aluminum foil very well.  With enough heat,
you can solder anything.  Too bad the aluminum foil won't hold up at that
temperature and neither will the solder.

       You now can solder leads to the BALUN or solder the coax direct to
the copper tape. 

       For an indoor antenna, the foil antenna works rather well.  It can
out perform a vertical and pull in the weak ones with ease.  I think you'll
find it one of the most inexpensive antennas you can build yourself.

73, Wayne, KB4YLY