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BOOTY MONSTER
10-19-2012, 03:01 PM
http://www.smeter.net/daily-facts/11/fact30.php

Tree Signal Attenuation

November 30th Fact-of-the-Dayf a vertical 28 MHz antenna is surrounded by moderately thick trees that are higher than the top of the antenna signals will be attenuated 2 to 3 dB on average. Tree attenuation with horizontal polarization under the same conditions usually will be negligible. At 144 MHz the same trees will attenuate signals 6 to 12 dB on average with vertical polarization and 3 to 4 dB with horizontal polarization. However, with vertical polarization at both frequencies and with either polarization at 144 MHz there will be large strength variations with small changes in antenna position due to standing waves caused by tree reflections. 2004 Martek International All rights reserved.
(http://www.smeter.net/daily-facts/11/fact30.php)

CBRN38
10-21-2012, 05:19 PM
i dont believe that is possible

BOOTY MONSTER
10-21-2012, 05:29 PM
what do you believe about tree attenuation ?

CBRN38
10-21-2012, 06:29 PM
i dont believe it because there is no way it can be true. Even though i havent done any of the field testing myself to verify the claims. I am still going to say this post is bull shit

High Voltage Mobile NJ
10-21-2012, 09:29 PM
both of you shut the fuck up . your posts are fucking stupid . :300 (245):

BOOTY MONSTER
10-21-2012, 11:14 PM
i dont believe it because there is no way it can be true. Even though i havent done any of the field testing myself to verify the claims. I am still going to say this post is bull shit

LOL . ignorance is bliss and you're happy just arguing with me ..... so childish .
BTW , your field testing and claims are laughable ,.

http://www.cbjunkies.com/threads/192-the-latest-merlin-commercial-.

BOOTY MONSTER
10-21-2012, 11:15 PM
both of you shut the fuck up . your posts are fucking stupid . :300 (245):

http://www.cbjunkies.com/threads/77-Forum-Rules-please-read!!!
(http://www.cbjunkies.com/threads/77-Forum-Rules-please-read!!!)
No Bullying - Do not pick on other members. The worst kind of bullying is where new members are picked on. This hurts the member as well as the board.

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CBRN51
10-22-2012, 01:28 AM
http://www.cbjunkies.com/threads/77-Forum-Rules-please-read!!!
(http://www.cbjunkies.com/threads/77-Forum-Rules-please-read!!!)
No Bullying - Do not pick on other members. The worst kind of bullying is where new members are picked on. This hurts the member as well as the board.

No Flaming - Flaming harms the nice atmosphere of cb junkies. It also causes thread's to go off topic, and most importantly, it hurts the person being flamed. The victom may defend themselves against any accusations made to them, but may not make any additional accusations to the flamer (which also counts as flaming).

No Profanity or Obscene Content - Such content does not belong on cb junkies. A censor system is in place as a backup. If you see words in your post being replaced with ****, you have done something wrong. Please edit your post and tone it down before your timer runs out. To edit a post, click the "Edit" button right below it. Cheating the censor system is against the rules.
bm i do believe that hi voltage is fully aware of the rules !
although it would appear that you have some difficulty understanding them ? as your constantly re-posting then , in a effort to spam and flame the integrity of the forum "air"
at certain members that offer simple debating

BOOTY MONSTER
10-22-2012, 09:39 AM
there was no debating . a debate offers evidence to support the differing opinion . cool breeze disagreed with nothing to offer other than he doesn't believe the article ...... and there's nothing wrong with that according to the rules here .

if hv is aware of the rules he should know not to cuss in the open forum and to also not bully or flame folks .

there is a section called "THE FIGHT CLUB" for that type of childish behavior ..... and for folks that cant add anything constructive to a adult conversation .

what are your thoughts on RF signals being attenuated by trees 5150 ?

doughboy
10-22-2012, 10:28 AM
I have to agree with booty on this it is well documented in arrl books as well as in some ham testing study guides now i cant really bitch at you for cussing hv cause it happens all over the board by everyone including myself and i should probably remove that rule but lets everybody play nice here in the sandbox

doughboy
10-22-2012, 10:30 AM
Forgot to mention this does depend on the distance the trees are from the antenna

BOOTY MONSTER
10-22-2012, 11:03 AM
Forgot to mention this does depend on the distance the trees are from the antenna

yep and the antenna too . something with a higher take off angle (like a vertical dipole , star-duster , merlin or other short/shortened 1/4 wave ground plane) would be less effected than a 5/8 or vector 4000 type antenna with a lower TOA that puts more signal on the horizon aka off to the side where other radio operators are located .... as opposed to the shorter antennas that shoot more signal up towards airplanes over-head . but , the taller antennas will have a better or much better chance of their upper sections clearing the trees to reduce or eliminate the effect of the trees ...... if the same feed-point height is used .

CandyBar
10-22-2012, 03:41 PM
Can one of you possibly explain what tree attenuation is exactly? I live in the woods, pretty much, so I should probably learn about this before choosing my base set up, if it's going to be affected by all the trees. My house is surrounded by mature pines (several acre around, actually).

CBRN38
10-22-2012, 04:03 PM
Lamens, the trees absorbing your signal

BOOTY MONSTER
10-22-2012, 04:28 PM
it's actually a reflection ... but absorption is good enough for laymen's terms :300 (287):
are you a believer now CB ? :300 (217):

CBRN51
10-22-2012, 05:39 PM
there was no debating . a debate offers evidence to support the differing opinion . cool breeze disagreed with nothing to offer other than he doesn't believe the article ...... and there's nothing wrong with that according to the rules here .

if hv is aware of the rules he should know not to cuss in the open forum and to also not bully or flame folks .

there is a section called "THE FIGHT CLUB" for that type of childish behavior ..... and for folks that cant add anything constructive to a adult conversation .

what are your thoughts on RF signals being attenuated by trees 5150 ?
antenna placement above tree line /canopy , would be a great start, or a stilh 660 chainsaw

BOOTY MONSTER
10-22-2012, 05:59 PM
i agree 5150 , but many folks can't do either of the options you suggested .

CBRN51
10-22-2012, 06:56 PM
one can always go higher
one can simply utilize a ground plane
one can get a ham ticket and seek help using the right to communicate laws / esda ?

one can use frequency enhancers rx amplification in conjunction with dsp filtration
one can hold hands and pray !

one can get copper nails and nail the trees in question ( will murder the trees)
one can poison the vegetation with copper sulfate or torodon solution
copper sulfate will kill trees - problem solved !

for where theres a will , there is a way !
we are CB'ers , and being so will do mostly as we see fit ..........until charlie visits with a NAL

CBRN51
10-22-2012, 06:57 PM
i agree 5150 , but many folks can't do either of the options you suggested .
booty SURE they can !

High Voltage Mobile NJ
10-22-2012, 08:38 PM
lol lol:drum:

CandyBar
10-27-2012, 06:26 PM
How much space should there be between the antenna and the nearest trees? I do have a big yard between my house and the tree line. There are only a couple of trees close to the house.

BOOTY MONSTER
10-27-2012, 07:03 PM
2 or 3 db of loss (or gain) isn't as noticeable as some folks tend to suggest . just stay as far from the trees as you can and go as high as you can . the money cost and physical effort to do so is typically the limiting factor

CBRN38
05-30-2017, 11:10 PM
if you have a frisbee golf style antenna trees will not affect you