aerial outside but not above the ridgeline

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radionortheast
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aerial outside but not above the ridgeline

Post by radionortheast » Mon Jun 26, 2017 10:06 am

I'm always hearing Albert banging on about getting an aerial inside, i'm just wondering if an aerial will still be effected, if the top of the aerial is below the ridge, but outside surely some of the signal would still be absorbed in that direction (into the roof), but is it just always better for an aerial to be outside regardless of the height?.

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Re: aerial outside but not above the ridgeline

Post by Maximus » Tue Jun 27, 2017 10:46 pm

It'll definitely be an improvement being outdoors. However, the signal is line of site as you probably already know. The higher you are (with less obstructions) the better. A good rule is, if your aerial can be seen, then you should be able to receive it.


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Re: aerial outside but not above the ridgeline

Post by McDonalds » Wed Jun 28, 2017 2:32 pm

our roof is about 5 floors high its to high to get up on to put a pole on the highest bit.
though have now managed to get my aerial just above the gutter line and its helped a lot getting the signal over the other side by over a mile or more.
I was on a garden pole before.
the signal isbetter than was in the loft and now rain should not effect as much if it does.

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aerial outside but not above the ridgeline

Post by Maximus » Wed Jun 28, 2017 11:13 pm

The topography also makes a big difference. E.g. If you live high up on a hill, then you'll be banging out on just a few watts :)


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Re: aerial outside but not above the ridgeline

Post by radionortheast » Thu Jun 29, 2017 5:48 pm

my aerial is about 20 cms lower than when it was in the loft, only been using 1.7w, already is the best i’ve had since been here, the signal seems more continuous than it did using 5w in the loft, its 20 cms lower than in the loft (the top of the aerial), the center of the aerial is about 1.3 meters off the loft floor, about 40% of the radial is still in the loft, i’ve been edging my aerial up gradually, i've been using a car radio hooked up the aerial and watching as it locks onto more signals as the aerial gets higher.

I loose my signal in town, I’m hoping might beable to reach it by moving the aerial higher without turning the transmitter up, might be asking alot since i’m not directly looking down on the town, on a shallow hill afew kms away. Did manage to get the aerial up an extra 5cms yesaday, hard to get anymore height for now without taking the tube down my aerial gose throught, its thick 5mm could only nibble a bit off with it up there. the angle of the radial pointing more down than it would be in the loft, this was the only way to get it up, didn’t seem effect it much. I’m abit concerned as the extra 5cms suqeezed out yesaday meant to swr went up to just over 1.3, guess thats not a whole lot of different since its been in 1.20's, its now 1.5w out. I have listenable signal in all directions about 8kms away, beyond it because of low audio, I can tell the signal is still there as noise gose low on my radio but its impossible to hear what song is playing.

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Re: aerial outside but not above the ridgeline

Post by Maximus » Fri Jun 30, 2017 7:45 am

Looks like you're on the right track. 1.5w is good for that distance. Maybe you should give it a bit more power. 5w shouldn't be a problem as long as the signal is clean.


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Re: aerial outside but not above the ridgeline

Post by Albert H » Fri Jun 30, 2017 3:02 pm

You should consider using some audio processing to get your mod level up but not over the top. You can do this with software like Stereo Tool (and many others too numerous to mention).
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Re: aerial outside but not above the ridgeline

Post by yellowbeard » Sun Jul 02, 2017 8:51 am

If you are looking to get into the town maybe you should consider a beam antenna, which you should be able to pick up cheap from the internet or you could make easily enough. An HB9CV is quite compact, tunes up well and can be made in an hour out of junk box parts and thick wire. Albert is spot on about using some audio processing to boost your listenability, even an old computer should be up to running the required software and the change will be dramatic.

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Re: aerial outside but not above the ridgeline

Post by Albert H » Sun Jul 02, 2017 12:11 pm

Albert H wrote: Fri Jun 30, 2017 3:02 pm You should consider using some audio processing to get your mod level up but not over the top. You can do this with software like Stereo Tool (and many others too numerous to mention).
Sorry - that was a very quick post from a phone.... If you use some audio processing, you'll get your audio louder, but without getting to the point of over-modulation. Your audio will have greater "density" and less dynamic range (not what you want if you're broadcasting Beethoven, but definitely what you want for modern music). The point is that a bit of compression and limiting will get your audio over the inherent noise - your audio will be more obvious even when the signal is weakened by distance.
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Re: aerial outside but not above the ridgeline

Post by radionortheast » Thu Jul 06, 2017 1:33 pm

thanks using stereo tool and taking out the clipper seems to of improved it alot, now hear the music when the signals weak, also cut about 5 meters off the coax, left some spare for coiling, it was about 20 meters long before, was keeping the power low while I sort out the signal, it is sounding good, i’ve yet find out what the signal is doing to the north east not beable to get that way.

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