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Topband: Battle Creek Special vertical as a simple tx antenna

To: <Topband@contesting.com>
Subject: Topband: Battle Creek Special vertical as a simple tx antenna
From: "George Taft" <w8uvz@voyager.net>
Date: Sat, 16 Jun 2007 22:55:45 -0400
List-post: <mailto:topband@contesting.com>
Hello Bill etal

As one of the three "principals" of the Battle Creek Special vertical loan 
program, I feel compelled to comment (hi).

I would agree with (WA4FKI) Bill's conclusion of the BCS as a simple tx 
antenna for low bands - by design.  It is simply a trapped vertical for 40 & 
80 m, and an inverted L for 160 m all rolled into one unit. Comes in a 
box/bag with guys, radials and a manual for construction - a low band 
vertical for DXpeditions - add RF via a piece of coax and....


I say by "design" since it is simple as stated - a single vertical using 
known antenna techniques to tx on those bands.  But as a practical matter, 
construction is not as simple.  One needs properly resonated traps, with 
some top loading for 80 m to make it all work. And the traps themselves are 
more complicated than they appear with an "L/C trap" that utilizes coils and 
coax stubs to provide the capacitance for the trap (stuffed inside the 
aluminum antenna tubing).  All this designed not to fail in subzero 
Antarctic regions as well as 130 deg heat on some Pacific islands.  And in 
100 mph winds if encountered. Average ham doesn't need all this to venture 
onto the lower bands.

Anyone who has tried to construct and tune a multiband commercially made 
vertical will understand that there is some difficulty involved in getting 
the antenna to resonate on all the desired bands at the same time.

Better u take your tx needs band by band and simply use a single vertical or 
inverted L to get the same tx result.

The "BCS" was originally designed to help DXpeditions gain  low band 
capability.  It was designed when many of the DXpeditions took triband yagis 
for upper bands and need a compliment for lower band operation.

Today's modern DXpedition carries monoband yagis for upper bands including 
40 m.  Some even utilize vertical arrays for each band.   Low bands may be 
covered with commercially made verticals that are mostly complete in their 
makeup (Titanex comes to mind, Force 12, DX Engineering etc).

Our BCS loaners are still available and work very well but the demand has 
certainly declined. They powered low band signals from such rare places as 
3Y5X, VK0IR, VP8SSI, YK0A, 3Y0PI, 5X4F, 3B7RF, 9M0C, FO0AAA, K5K(Kingman), 
TX0C, FT5XO and over 30 other places.

But we have never recommended that hams copy the design for use as a low 
band tx antenna.  Not that we would mind and would, in fact, be flattered.

Use a wire hung as an inverted L or build a single band vertical  - all with 
plenty of radials.  Or try "shunt feeding" an existing tower for low bands. 
All good choices that ON4UN's book describes.

 73  George  W8UVZ 

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