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#1




Antenna Length Formula
Folks, I'm old, I'm tired, and I'm lazy. I'm also forgetful.
Would someone kindly provide the formula for deterring the length of a fullwave antenna for a given frequency ( a fullwave whip comes to mind)? Then, I can do the math. Better yet, I'll give you the frequency and _you_ can do the math. It's 160.890 mHz. I will never ask this question again. Sorry. Thanks, etc. Best,   Don Forsling "IowaGateway to Those Big Rectangular States" 
#2




Try this.
http://www.crompton.com/wa3dsp/hamradio/antcalc.html "Don Forsling" wrote in message ... Folks, I'm old, I'm tired, and I'm lazy. I'm also forgetful. Would someone kindly provide the formula for deterring the length of a fullwave antenna for a given frequency ( a fullwave whip comes to mind)? Then, I can do the math. Better yet, I'll give you the frequency and _you_ can do the math. It's 160.890 mHz. I will never ask this question again. Sorry. Thanks, etc. Best,   Don Forsling "IowaGateway to Those Big Rectangular States" 
#3




234 / frequency in MHz
234/ 160.890 = 1.45 Ft "Don Forsling" wrote in message ... Folks, I'm old, I'm tired, and I'm lazy. I'm also forgetful. Would someone kindly provide the formula for deterring the length of a fullwave antenna for a given frequency ( a fullwave whip comes to mind)? Then, I can do the math. Better yet, I'll give you the frequency and _you_ can do the math. It's 160.890 mHz. I will never ask this question again. Sorry. Thanks, etc. Best,    Don Forsling "IowaGateway to Those Big Rectangular States" 
#4




"sean" wrote in message ... 234 / frequency in MHz 234/ 160.890 = 1.45 Ft He is asking for the length of a full wave whip so multiply the above X4. However, bear in mind that full wave whip will: 1. Be more difficult to feed as its end Z is around 1K Ohm or higher. 2. Have less gain than a 1/4 wave antenna at useful elevation angles. Dale W4OP 
#5




physsics to the rescue
300/frequency in mhz gives length in meters the 300 comes form the lv=c calculation using above a 900mhz frequench has wavelength of .3 meters I prefer to work in metric because everything is base 10 as in 100 centimeters in a meter but there are not 10 inches in a foot and not 1000 inches in a mile......math is easier in metric Don Forsling wrote: Folks, I'm old, I'm tired, and I'm lazy. I'm also forgetful. Would someone kindly provide the formula for deterring the length of a fullwave antenna for a given frequency ( a fullwave whip comes to mind)? Then, I can do the math. Better yet, I'll give you the frequency and _you_ can do the math. It's 160.890 mHz. I will never ask this question again. Sorry. Thanks, etc. Best, 
#6




Antenna Length Formula

#8




Antenna Length Formula

#9




Antenna Length Formula
if it's for RX the imp matters not
mike wrote in message ups.com... 2808 divided by the frequency in MHz will give the length in inches for a 1/4 whip. Roughly 17.5 inches. Times 4 will give you a full wave. Can't understand why you would want a full wave whip. The impedence would be very high and would not match a scanner or two way radio. 1/4, 5/8, or 3/4 in much easier to match. Jim, K5DIE/9 Al wrote: (Don Forsling) wrote in : Folks, I'm old, I'm tired, and I'm lazy. I'm also forgetful. Would someone kindly provide the formula for deterring the length of a fullwave antenna for a given frequency ( a fullwave whip comes to mind)? Then, I can do the math. Better yet, I'll give you the frequency and _you_ can do the math. It's 160.890 mHz. I will never ask this question again. Sorry. Thanks, etc. Best, Once upon a time when I was taught physics, I was told that full wave lenght should be calculated by dividing the speed of a light (299820km/s) with the frequency(in MHz)/1000, so for full wave dipole it should be 299820*160.89/1000=1.864m, for halfwave dipole divide the result by two. Albert 
#10




Antenna Length Formula
On Thu, 06 Oct 2005 17:34:46 GMT, "mikeFNB"
said in rec.radio.scanner: if it's for RX the imp matters not That old nonsense again? SWR isn't directional. Of course impendence matters, unless you don't care how much signal you lose between the source and load. 

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