[amsat-bb] Re: AO-07 Downlink Antenna

[Edward R. Cole]

At 04:31 PM 2/3/2007 +0000, w7lrd at comcast.net wrote:
>
>Tyler-Think about a 10 meter full wavelength loop inside 1/2 inch pvc
laying on your roof.  I used one for many years on rs10 and 15.  A little
more gain and less directive than a dipole.  The length will be 1005/F(mhz)
>73 Bob W7LRD
>Seattle
>
>-------------- Original message -------------- 
>From: "Tyler Harpster" <tyler881 at adelphia.net> 
>
>> I just bought a 10 meter preamp from Advanced Receiver Research. I was 
>> planning on making a 10 meter dipole and feeding the voltage supply for
the 
>> mast mounted preamp up the coax. Will this be enough to hear the bird? 


Bob,

I guess the height of the horizontal loop works well for a NIV antenna
(beaming high angles).  I have thoughts of putting up a 10m J-Pole using a
ten foot tower section as the base and extending with 1-Inch aluminum
tubing for the required length (3/4 wavelength total).  This will likely
provide lower radiation angles (which is desirable for DX).  The J-pole
does not require a ground plane so hoping this will work well.  A J-Pole
works well using a flagpole as a stealth antenna - just use the top section
length as required at the operating freq.

Tyler,

My experience with ARR preamps is with models not set up for coax line
powering.  If you are uncertain, you might check on this.  To use coax line
power with a preamp not providing the required circuitry one must add
T-bias units on both ends of the coax (unless your radio has the capability
of powering an external preamp).
73's,
Ed - KL7UW 
=========================================
BP40iq,  Nikiski, AK      http://www.qsl.net/al7eb
Amsat #3212
Modes: V - U - L - S
USA Rep. for Dubus Magazine: dubususa at hotmail.com
=========================================