Subject: Re: [TowerTalk] 2 el yagi question
Tom If you put a director in front of a dipole you have constructed a two
element Yagi antenna. Assuming you use the proper spacing (0.1 to 0.15
wavelengths) between the dipole (now called the driven element) and the
director (which is about 5% shorter than the dipole) and you match the
antenna to the coax (gamma match maybe) the gain will be about 5 dB greater
than a dipole. A signal off the back of the antenna would be down about 10
dB compared to a dipole. Remember that an S Unit is equal to 6 dB. If you
are interested in Yagi antennas there are many good sources but a good older
book is the "Beam Antenna Handbook" written by William I. Orr, W6SAI (now
SK) and Stuart D. Cowan, W2LX. You can also read up on Yagi antennas and
many others in the ARRL Antenna Handbook. You might also want to search on
Google for "Wire Yagi Antennas". If you are thnking about a Field Day
antenna you might look at this
link.[http://www.qsl.net/ve3rgw/field98/beam.html] 73 and good luck. Ron
W8RJL
> ----- Original Message -----
> From: "Tom Osborne" <w7why@frontier.com>
> To: "Towertalk" <towertalk@contesting.com>
> Sent: Thursday, May 17, 2012 7:42 PM
> Subject: [TowerTalk] 2 el yagi question
>
>
>> OK, this may be a dumb question, but I've been wondering.
>>
>> Say I put up a dipole going E and W, and there's an S-9 signal on the
>> dipole coming from the South.
>>
>> If I put a director in front of the dipole, will the signal still be S-9
>> on the dipole?
>>
>> Just wonderin'. 73
>> Tom W7WHY
>>
>>
>>
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