Can I tune 10,12, 15 and 17 $& 20 m?

Just what it says -- this is the place for any discussions not related to Buying, Selling and Trading ham gear. The discussion must be related to Ham Radio.
Post Reply
KC6NEN
Posts: 21
Joined: Thu Oct 20, 2016 10:52 pm

Can I tune 10,12, 15 and 17 $& 20 m?

Post by KC6NEN »

I am trying to design a dipole with traps/loading coils for 160-10 m. Can I probably tune 10, 12, 15 M with the same length of wire?
Can I probably tune 17 and 20 meter with the one wire length?
This would save designing/building/ inserting 3 traps.
k9yli
Posts: 229
Joined: Fri Aug 12, 2005 11:35 pm
Location: northwest wisconsin

Re: Can I tune 10,12, 15 and 17 $& 20 m?

Post by k9yli »

If you chart out the lengths you will see some multiples of length. 40 and 15 are related..
as are 10 and 20 or 40 and 80.
Simpler antenna would be a fan dipole. one feed point, multiple wires cut to length..
Plus a lot of weight for that many traps.. Think separate antennas.
An 40/80 trap dipole,(because later on even with multiple band beam, 160 /80/40 will still be wire antennas.)
Lots of planning before you start building these antennas..
ku3x
Posts: 37
Joined: Sat Mar 24, 2012 5:43 pm

Re: Can I tune 10,12, 15 and 17 $& 20 m?

Post by ku3x »

Building and all band trap antenna is do-able. "Is it your best choice?" Probably not. You'll pretty much need a set of traps per band. With every trap you make the antenna shorter. Now you narrow the bandwidth per band. More traps, each band looses bandwidth. A tuner does not correct this problem.
You'll have SWR issues and with high SWR on coax you increase the losses. Again, a tuner does not correct this problem.

Your best choice for an all band antenna is to erect a flat top dipole, for the lowest band of operation and feed it with parallel feeders.
The parallel feeders should be terminated at the transmatch, commonly misnamed an antenna tuner.

Barry, KU3X
www.ku3x.net
Post Reply