Home |
Search |
Today's Posts |
#1
|
|||
|
|||
Scanner Antenna in Tree
Hi. I live in a wooded park like neighborhood in suburban detroit mi.
Birmingham to be exact. My neighbor gave me a huge live pine tree that is probabaly close to 100' feet tall, at least exactly double the high voltage wires on the power pole's height. I am in the top ten percent of trees height for many miles, but not eneugh to see the horizon. I am going to mount a scanner antenna and a tv antenna in this tree for my scanner and tv/fm use. Can anyone give me some reccomendations as to how to do this? Thanks, Bud |
#2
|
|||
|
|||
haha she dosent care, and said that the aerial wires can go from the
tree to my radio hut in the air. I wish it could be moved |
#3
|
|||
|
|||
haha she dosent care, and said that the aerial wires can go from the
tree to my radio hut in the air. I wish it could be moved |
#4
|
|||
|
|||
On Wed, 17 Aug 2005 04:50:54 -0400, "Zombie Wolf" said
in rec.radio.scanner: Here is how you go about this task. First, we need a support for the coax, especially if you have to run over 125 feet of it. this is usually done by running a cable from the tree to a post firmly embedded in the ground right next to your house. We then support the coax by whipping it around and around this cable, to take the strain off it. We literally wind the coax around the cable Bad idea - you're forming a pretty good choke at anything above VHF-lo. Use steel wire to wrap both the coax and the messenger wire (that's what it's called - it's usually 14k stainless "aircraft" cable) to each other. Suggestion for the climber: Assemble whole pipe and antenna on the ground, then when in position in tree, use rope to "haul" antenna and pipe up to your position. Start with pipe and antenna upside - down, and install first bolt , but not completely tight. then, climb a bit further up, and use rope to turn whole thing right side up by rotating on installed lag bolt. Install second lag bolt and tighten. Good if there's enough room between foliage, otherwise haul it up right-side-up. One problem - it sounds as if the coax is going to have to be long enough that, even with LMR600, it might not be better than an antenna mounted lower but much closer. |
#5
|
|||
|
|||
Here is how you go about this task.
First, we need a support for the coax, especially if you have to run over 125 feet of it. this is usually done by running a cable from the tree to a post firmly embedded in the ground right next to your house. We then support the coax by whipping it around and around this cable, to take the strain off it. We literally wind the coax around the cable next, if you can get someone to climb the tree, you should have them mount the antenna pipe to the tree, in the following manner: 1st method: drill a couple of holes thru the antenna pipe , one a foot or so from the bottom , another a foot from the top. 1/4 inch holes work well. Get some 3 or 3 1/2 inch, quarter inch lag bolts from the local hardware store. Screw these thru the antenna pipe into the tree trunk until tight. You probably should have the antenna on the pipe when you do this, and should hook the coax up also. A good strain relief for the coax at the bottom of the pipe would consist of a couple of regular mercy clamps, with rubber inserted under them between the coax and the clamp. This will take the pull from the coax . Do not over-tighten the clamps as this will tend to crush the coax too much and destroy its impedance and performance. Use good coax, like Belden 9913 for this, since losses in coax tend to be high at scanner frequencies if you dont use good stuff. Suggestion for the climber: Assemble whole pipe and antenna on the ground, then when in position in tree, use rope to "haul" antenna and pipe up to your position. Start with pipe and antenna upside - down, and install first bolt , but not completely tight. then, climb a bit further up, and use rope to turn whole thing right side up by rotating on installed lag bolt. Install second lag bolt and tighten. Hook up coax, weatherproof connection, and install mercy clamps near bottom of pipe, with coax going thru them, and rubber in place. You are done. Come down and have beer, it has been a VERY good day in scanner land...... wrote in message oups.com... Hi. I live in a wooded park like neighborhood in suburban detroit mi. Birmingham to be exact. My neighbor gave me a huge live pine tree that is probabaly close to 100' feet tall, at least exactly double the high voltage wires on the power pole's height. I am in the top ten percent of trees height for many miles, but not eneugh to see the horizon. I am going to mount a scanner antenna and a tv antenna in this tree for my scanner and tv/fm use. Can anyone give me some reccomendations as to how to do this? Thanks, Bud |
#6
|
|||
|
|||
One problem - it sounds as if the coax is going to have to be long
enough that, even with LMR600, it might not be better than an antenna mounted lower but much closer. I am going to go and measure again, but assuming I measured wrong before, Is a 100 foot run too long for the antenna to work properly? I am probabaly going to use 300 ohm twin lead for the lead in, unless people think it should really be coax. See a picture of the proposed set up at http://community.webshots.com/photo/...24626583NExHgY |
#7
|
|||
|
|||
I see no one took in the concept that this might just turn into one helluva a lightning rod!!!!!!!!!!! |
#8
|
|||
|
|||
said
On 15 Aug 2005 17:55:42 -0700, wrote: My neighbor gave me a huge live pine tree that is probabaly close to 100' feet tall, at least exactly double the high voltage wires on the power pole's height. i'd like to hear the reccommendations on how to move the tree from his yard to yours I was thinking the same thing. I guess it depends on what the definition of "gave" is. ;-) |
#9
|
|||
|
|||
I've strung a wire either between two trees while at a city park or
between the house nad a tree for a shortwave antenna scanner antenna usually wavelengths are 4 meters or less and a 2 meter ham or 2m/440 antenna will work just fine an antenna for 150mhz will work for 300, 600 even 900mhz as it is a multiple of the wavelength the antenna does not have to be exact but hte cloer the better wrote: One problem - it sounds as if the coax is going to have to be long enough that, even with LMR600, it might not be better than an antenna mounted lower but much closer. I am going to go and measure again, but assuming I measured wrong before, Is a 100 foot run too long for the antenna to work properly? I am probabaly going to use 300 ohm twin lead for the lead in, unless people think it should really be coax. See a picture of the proposed set up at http://community.webshots.com/photo/...24626583NExHgY |
#10
|
|||
|
|||
|
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Inverted ground plane antenna: compared with normal GP and low dipole. | Antenna | |||
Yaesu FT-857D questions | Equipment | |||
R75 Antenna | Shortwave | |||
QST Article: An Easy to Build, Dual-Band Collinear Antenna | Antenna |