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Author Topic: 4btv with ham sticks  (Read 1202 times)
AE7IS
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Posts: 48




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« on: April 03, 2013, 09:05:34 PM »

Once upon a time I thought I saw a project using a 4btv with ham sticks as the counterpoise.  And as these things always go, I remember that it worked quite well, easy to tune and all that.  A magical antenna so to speak.  Does anyone remember that work-up? and if so their thoughts?  ANd finally, just how was it done?
thanks all
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M6GOM
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« Reply #1 on: April 04, 2013, 03:23:03 AM »

Only an option if you're mounting it up in the air. If you're ground mounting it is a waste of time and money.

Easiest way to do it is to get a square or round slab of metal and have the appropriate number of 3/8" tapped holes put in to mount the hamsticks. Tune each for lowest SWR on the relevant band and pop them in. Hook the braid of the co-ax up to the block and mount the whole lot directly below the 4BTV as close as possible.
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W5DXP
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« Reply #2 on: April 04, 2013, 04:31:01 AM »

A magical antenna so to speak.

There are no magical antennas. If one sounds like magic, it is an illusion. It would work well only if elevated and only on the bands where a hamstick is an efficient radiator, i.e. 20m-10m.

Using a hamstick for a counterpoise on 80m or 40m is somewhat like having one buried radial as the efficiency of an 80m hamstick is in the ballpark of 1%. The beauty of two 1/4WL elevated radials physically opposing each other is that a lot of the RF radiated by each radial is canceled by the other radial and returned to the system to be radiated by the vertical radiating element. An 80m or 40m hamstick radial cannot do that.
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73, Cecil, www.w5dxp.com
The purpose of an antenna tuner is to increase the current through the radiation resistance at the antenna to the maximum available magnitude resulting in a radiated power of I2(RRAD) from the antenna.
AE7IS
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« Reply #3 on: April 04, 2013, 10:11:32 PM »

Can I then assume that I would gain nothing by doing this?  Currently my 4btv is roof mounted with 4 cut radials per band.
thanks for the input.
frank
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W5DXP
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« Reply #4 on: April 05, 2013, 05:45:49 AM »

Currently my 4btv is roof mounted with 4 cut radials per band.

Adding a hamstick counterpoise to that configuration would either have little effect (on the higher frequencies) or make things worse (on the lower frequencies). If you want better performance on the higher frequencies, IMO, erect a rotatable dipole.
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73, Cecil, www.w5dxp.com
The purpose of an antenna tuner is to increase the current through the radiation resistance at the antenna to the maximum available magnitude resulting in a radiated power of I2(RRAD) from the antenna.
AE7IS
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Posts: 48




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« Reply #5 on: April 05, 2013, 08:37:06 AM »

ok, thanks. 
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WB4TJH
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« Reply #6 on: April 06, 2013, 06:36:40 PM »

Keep the full length radials as they will limit losses you will find in the shortened hamsticks. The way you have your antenna now is the best way you can put it up.
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