Bob - Yes there is a 14AVQ antenna. It is a trap vertical for 40, 20, 15,
and 10 M. No WARC bands are included as they were not even imagined when
the antenna was designed in the early 60s. They were made by HyGain (now
Telex?) in Lincoln Nebraska who might still have parts and or manuals
available. They advertise in QST. I used three of them phased in a
triangular array 30 years ago as a novice, WA0MWN, in South Dakota. My Dad,
WA0OML, still uses one of them which I recollect has been up since 1966 or
so. It still works fine despite missing one or more of the spokes in the
top hat. One of the other two 14AVQs was pulled down by vandals about 10
years ago or so. The other one had one of the plastic insulators in the 40
M trap crack about 20 years ago after an ice storm. I think they hold up
excellent particularly given that climate. The two remaining antennas were
given to a local ham who made one good antenna out of them. I think he is
still using it.
They are good performers as ground mounted verticals go, with 16 quarter
wave radials on 40 M. My Dad has replaced the two antennas which failed
with a Butternut which appears to perform slightly worse than the 14AVQ,
and an R-5 which appears to perform slightly better. This is based on some
comparitive measurements I made on 20 M with the DX beacon network.
If you don't have a manual you may wish to look for an article by Jerry
Sevick (sp?) in QST in the early 70s which described some modifications to
the 14AVQ which slightly improved efficiency and raised feedpoint impedence
on 40 M. A set of dimensions are also given there.
You may wish to inspect the traps for damage and replace cracked
insulators. In particular the top insulators should be good with no cracks
or else water will get into them and change the operating point during
rainy spells. Cracks in these insulators can be fixed with RTV, Bathtub
Caulk, or Gasket compound. If you can disassemble the traps you may wish to
do so to remove any insect nests that can accumulate over the years,
particularly in storage. A good scrubbing with soap and water followed by a
mild bake out in a 150 F or lower oven will help as well.
Also check for DC continuity across the feedpoint. HyGain put an RF choke
here to provide lightning protection. If it is open you may wish to replace
the choke or substitute a 2 W 20 KOhm to 50 KOhm resistor. You can leave it
open, but you should be aware that the antenna is not at DC ground.
As I said, Hy Gain may still have the manual available. You may wish to
peruse old QSTs for 14AVQ ads to see how it is supposed to look.
Setting it up without the manual should not be hard though. You can start
with the lower portion, no traps, and adjust it for resonance at 10 M. It
will be slightly less than 8 feet or so long. Add the 10 M trap and recheck
the resonance. Adjust the tubing length below the trap as necessary. Add
more tubing above the 10 M trap for 15 M resonance. Add the 15 M trap and
check for resonance. Adjust only the tubing between the 10 M and 15 M trap.
Add tubing above the 15 M trap and adjust for 20 M resonance. Add the 20 M
trap. Adjust the tubing between the 15M and 20M trap if necessary for 20 M
resonance. Add the tubing above the 20 M trap for 40 M resonance. There was
a three element tophat about a foot in diameter on top originally. If you
have this you can use it, if not just add extra lengths of tubing. If you
don't want 40 M operation, but want 30 M, adjust the top tubing for 30 M
resonance rather than 40 M.
I should emphasize here that when tuning multiband antennas better is the
enemy of good enough. If you go back to a previously adjusted band to get
slightly better performance you will invariably make another band worse.
Changing that band will make another band worse, and you will rapidly have
a nonconverging problem. If you follow the above procedure and are unhappy
with the results, start all over again. You may wish to change the point or
points where you put the resonances in each band to put it where you like
it in one particular band. YOu may have to go through the above exercise
twice or so before you are satisfied.
As I recall HyGain provided two sets of lengths, one for CW and one for
Phone. Also as I recall the corresponding lengths were not always
intuitively consistent with which portion of the band was chosen. I think
that some of the phone lengths were longer than the CW lengths.
As with all endeavors, upon getting frustrated, stop, go into the house, go
to the refrigator, get the cold beverage of your choice, relax, and tell
anyone who asks that things are going fine. After the beverage is half
completed start thinking about your problem and formulate a rational
approach to solving it. Asking for help from an experienced antenna pruner
is always an alternate.
When putting the tubing together you should probably clean the aluminum
with Steel Wool or Scotch Brite and use a conductive grease available from
an electrical supply house.
If you are missing any of the tubing you can replace it with standard
sizes. These can be obtained from a metals dealer or ordered from Texas
Towers. If you are missing some traps you can omit them, you just won't
have coverage of that band. Replace the missing trap with a slightly longer
piece of tubing.
HyGain used a clamp mechanism that put a dent in the two tubes. This dent
usually has to be drilled out to uncouple sections. Sometimes people just
cut it off, resultin in substantial tubing loss. The clamps may still be
obtained from HyGain, I don't know. If not, slitting the ends of the tubing
and using hose clamps (Jubilee clalmps for you G's) will work fine. Look at
the handbook for ideas.
At any rate you don't need the whole antenna to have something useful. The
base with the feedpoint, and mounting bracket are quite useful for any
vertical antenna project. The HyGain traps were very good with relatively
low loss. Often one sees parts of antennas; particualrly traps and
feedpoint brackets at HamFests which can form the basis of a good
inexpensive antenna.
I suggest mounting the antenna up high, on the roof if possible. If mounted
5 feet or higher above ground 2 radials per band should be sufficient. I
would add a 1:1 current choke at the feedpoint to minimize feedline
radiation. 12 turns of coax thorough a ferrite core should work, as will a
simple coil of feedline. THe hand book lists several designs for air core
choke baluns that were designed by W7EL I think that should also work.
Good Luck. Let us know how it rturns out. - Duffey KK6MC/5
James R Duffey KK6MC/5 DM65
30 Casa Loma Road
Cedar Crest, NM 87008
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