Up to a point it does but thaere is a point where the extra cable involved to get that antenna higher has more loss that you gain by the added height. Granted for CB it is not nearly as bad as for VHF/UHF.
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Antenna Height VS Coax Length
- Thread starter Cajun Invader
- Start date
Up to a point it does but thaere is a point where the extra cable involved to get that antenna higher has more loss that you gain by the added height. Granted for CB it is not nearly as bad as for VHF/UHF.
some times lower is better
as a general rule (once you get above wl/2) ,.... that is not always correct, unless you specify the frequency.
@ vhf & above, i'll agree with it. but, @ HF it isn't always correct. i can raise or lower my antenna with a push of a button from my operating position, and many times lower is better.
higher antenna = lower radiation angle = better DX qualities.
lower antennas can have a much higher radiation angle (NVIS) and make excellent antennas out to about 800 miles or so.
btw, i'd be real careful with that section of tower with the bent legs
as a general rule (once you get above wl/2) ,.... that is not always correct, unless you specify the frequency.
@ vhf & above, i'll agree with it. but, @ HF it isn't always correct. i can raise or lower my antenna with a push of a button from my operating position, and many times lower is better.
higher antenna = lower radiation angle = better DX qualities.
lower antennas can have a much higher radiation angle (NVIS) and make excellent antennas out to about 800 miles or so.
btw, i'd be real careful with that section of tower with the bent legs
Another aspect that deserves a little thought is the stability of the supporting device (tower/tree). Unless it's really not done right, the tower will always have less movement than a tall tree. that isn't exactly the most critical part of it, but it certainly does play a part in how long whatever is at the top of that swaying thingy stays there.
- 'Doc
And don't misunderstand! I wish I had that tree in my yard, and all things considered, since I don't have a tower, I'd probably use it. IF I could find someone to climb it for me, I ain't doing that!
- 'Doc
And don't misunderstand! I wish I had that tree in my yard, and all things considered, since I don't have a tower, I'd probably use it. IF I could find someone to climb it for me, I ain't doing that!
btw, i'd be real careful with that section of tower with the bent legs
Good eye! I was wondering how long it would take someone to notice that.
Already taken care of. I put some heat on the legs and bent them back. The previous owner used a ratchet strap to secure it when he moved it and bent them in.
Where I'm from radiated squirrel is considered and delicacy.
I like bishops' idea about the pvc conduit if you chose the tree installation and it works in underground installs also but there is a condensation matter there but does deter rodents.
Not knowing the radiation pattern and projected take off angle of radiation it's any ones' guess as to the proper height to mount this mysterious antenna, meaning the 55 merlin.
Well..
This is where my Crazy Coax-feedline Truly comes into play
Andrews Heliax (what i use for HF as well as VHF & UHF)
For HF (in this case for 27 Mhz)
at 30 Mhz one sees a loss of 0.195 Db per 100 ft
or 0.641 Db for 100 meters (333 ft)
( would be a little lower loss given you would be transmitting 26,905 to 27,405 Mhz)
This is not ( as was pointed out cheep stuff )
But comes with a 10 year guarantee
I like your plan to use the tower for the beams and the tree for vertical.
I like using PVC pipe to keep coax clear of critters..lol.
There is another advantage to using the tree (for vertical) beyond the lowered take off angle.
Seems nearly all tree installed Verticals Obtaining Excellent natural Grounding carituristics (over and above using a grounding rod..that you still will need to use)
It is sought of like the natural advantage afforded from salt water grounding
Anyways...
Keep the tower for the beams.
Use the tree for the vertical (perhaps to be bold enough to put a Interceptor I-10K up there)
Good Luck however you do it..
Let us Know which way(s) you went
This is where my Crazy Coax-feedline Truly comes into play
Andrews Heliax (what i use for HF as well as VHF & UHF)
For HF (in this case for 27 Mhz)
at 30 Mhz one sees a loss of 0.195 Db per 100 ft
or 0.641 Db for 100 meters (333 ft)
( would be a little lower loss given you would be transmitting 26,905 to 27,405 Mhz)
This is not ( as was pointed out cheep stuff )
But comes with a 10 year guarantee
I like your plan to use the tower for the beams and the tree for vertical.
I like using PVC pipe to keep coax clear of critters..lol.
There is another advantage to using the tree (for vertical) beyond the lowered take off angle.
Seems nearly all tree installed Verticals Obtaining Excellent natural Grounding carituristics (over and above using a grounding rod..that you still will need to use)
It is sought of like the natural advantage afforded from salt water grounding
Anyways...
Keep the tower for the beams.
Use the tree for the vertical (perhaps to be bold enough to put a Interceptor I-10K up there)
Good Luck however you do it..
Let us Know which way(s) you went
Well King, your totally idealistic thinking is still alive and well. You are arguably wrong on just about everything you said here, except maybe for the specs on the Heliax and the part about its $ cost and I would even check that out.
The first sentence is for sure true, but in your pursuits for perfection I am surprised you didn't include the word "ideas" in the middle of your sentence---that would have made your statement almost perfect.
Height can have some affects on TOA, but in this case with only about 20' of height difference---it would likely be a marginal difference at best. Pointing to TOA makes a poor argument that is absolute for antennas in the real world and that is why a discussion on location is typically brought up. Except in theory, TOA is next to impossible to prove without a lot of effort and expense. Aside from all the lies associated with gain figures in CB, the importance of TOA is probably the best example of CBBS misinformation. Just ask ‘Doc, he tells it pretty well.
Trees are often struck by lightning, but that does not make them a particularly good ground. Even the tree's water content does not make what we would call a good conductor. Every tree that I have ever seen that had an antenna in it and that was hit by lightning---affected the tree the same way as long as a feed line was attached to the antenna. The lightning took the path of the feed line all the way to the end or the Earth. There are more details of what happened, but there were no exceptions in maybe 10 incidents I have seen. Typically only a branding type mark was left in the bark where the coax touched the tree.
I have no idea of what claims you would make when you talk about; "the natural advantage afforded from salt water grounding," but I would like to hear a few words from you on that subject. Would you be discussing in detail about putting a ground rod into some salt water at the beach somewhere, or how you would make a good Earth ground using a 5 gal bucket of salt and sand to tag around in your mobile setup, or maybe even salting the ground around your base antenna?
Cajun, there are two places you don’t want to put a big conductive antenna: 1) on the roof or your home or garage, and 2) attached to a possible $5-10,000 tree like the pine I see. You use to be able to charge of the loss of a tree on your property, but I don’t think you can do that any more. Your insurance probably won’t do anything but maybe allow you some chump change to remove one either, and if you have a fire on the house and the antenna is at the center of the possible cause, the insurance likely will not help pay for that either. Knowing the attitudes of insurance companies today, not wanting to pay, just having an antenna on your roof could give them cause to deny a claim.
Just reinforce your bent-up tower and use that along with your pushup pole.