[80m] Re: 4 square

Mon, 7 Jan 2002 07:57:36 +0100

> 	I think the performance of you 4 sq sounds just about right.
> 	Forexample, a flattop (Dipole) at 130 ft should theoreticaly
> 	beat a 4 sq with about 3 dB, they also have just about the
> 	same wave angle. 
> 	Calculation is like this, dipole at 0.5 wl gives about 7 dBi,
> 	4 sq gives a little over 5 dBi and I�ll subtract 1 dB for ground
> 	losses, thats 3 dB in favour for dipole.
> 
> 	73, Jim SM2EKM
> 	----------------------------------------------------------
> 
> 	-----Ursprungligt meddelande-----
> 	Fr�n:	[email protected] [SMTP:[email protected]]
> 	Skickat:	 den 7 januari 2002 01:18
> 	Till:	[email protected]
> 	�mne:	Re: [80m] 4 square
> 
> 
> 	Hi all.  I have a 4-square made of Rohn-25 tower and aluminum
> 	stingers.  It is an elevated system (16 feet).  My QTH is on a hilltop
> 	that drops off quite fast.  For example, the 4-square is centered on the
> 	hilltop, and some of the radials are as high as 50' off the ground at
> 	their tips.  
> 
> 	The system has worked fairly well for me, but isn't great to Europe.  For
> 	example, K4XS in Florida with 4 element quad fixed on Europe at 160' is
> 	constinently 10DB louder than me.  W8JI with a flat top dipole at 150' is
> 	normally 1 s-unit louder.  
> 
> 	On the other hand, my 4-square works great on long haul stuff like that
> 	JT1CO last week.  Many examples over the years have enforced this
> 	fact.  
> 
> 	One thing that I did this year that seemed to make a big difference on the
> 	pattern of my array was detuning all of the towers around the 4-square.  A
> 	friend of mine (W4OC) does this kind of thing for a living, so he offered
> 	to help.  We used a tunable field strength meter that Don had and tuned a
> 	shunt capacitor and wire on the tower for minimum radiated power measured
> 	on the FS meter.  The 4-square now has much more F/B than before, and is
> 	starting to act like other 4-square I have used with ground mounted
> 	radials and free of interaction from nearby towers.  
> 
> 	The past two seasons I was able to work my station remotely over a
> 	telephone remote link, but a lightning strike over the summer took out
> 	most of the remote hardware.  I'm just about ready to put it back on the
> 	air again.  Hope to see you all on the band when I do.
> 
> 	73
> 
> 	Bill Fisher, W4AN
> 	http://www.w4an.com
> 
> 
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