One should also consider the overall signal strength of the intended channels/system(s). You can afford a bit more coax loss with a really strong signal. And good antenna location and choice will influence this as well.
All my RX path questions
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G7RUX
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Indeed. LMR240 is only 1.9 dB more loss and RG213 is only 1.4 dB more.
I’m not sure what the costs are like for you in the US but here in the UK the extra cost of 600 over 400 is about 25% and for me that extra cost is worthwhile because that little reduction in loss comes at a small marginal cost with little or no extra effort for installation.
So I would go back the the overall advice which is to do the best you can *reasonably* do with regards to the feeder.
If the preamp is at the radio end it’s a waste of a preamp but if the preamp is at the antenna end you can have 10dB of coax less nd the preamp can make up for all of it.
G7RUX
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Yes, I know. (35+ years in RF R&D)
paulears
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There's also a balance on the actual receiver. If you elect to spend the money, then hanging a basic, low spec receiver on the end is sort of a bit pointless - as getting decent signals into a poorer receiver often produces unexpected results - the strong signals that show up the receiver's poor selectivity and other things.
G7RUX
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Of course. The OP gave no indication regarding the receiver, save IIRC that they are looking to receive a P25 system. This is why I said “do the best you reasonably can” with the emphasis on “reasonably.”
Going to the effort of installing feeder and not installing something at least half decent would seem to be daft and receivers are easy to swap out if needed, whereas upgrading feeder is a much more labour intensive process. If going to the trouble of installing feeder to an antenna there is no sensible reason why you would not use something decent. You could always pop attenuation or filtering at the receiver location if you wanted to go that way, although any preamp absolutely must go at the head end and should itself be appropriately filtered.
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AB5ID
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Certainly a Yagi antenna seems like the way to go. However, I'm curious whether the towers are positioned in the same general direction. If they are, it might be challenging to distinguish one from another. In such a scenario, opting for a slightly weaker signal could be preferable if it helps avoid picking up signals from unwanted towers.
I suggest starting with a Yagi antenna that you can easily return. Connect it to a short, inexpensive coaxial cable run outside (assuming you already have some available). Test if you can detect signals from the nearest tower with this setup. If not, you can then build on this by gradually increasing the antenna height to improve reception.
I suggest starting with a Yagi antenna that you can easily return. Connect it to a short, inexpensive coaxial cable run outside (assuming you already have some available). Test if you can detect signals from the nearest tower with this setup. If not, you can then build on this by gradually increasing the antenna height to improve reception.
Bonkk083 we are not at your location we do not know what transmitters are near your site. But if you are going to have a 3db loss then very little over 3db of gain as we have warned and warned about too much gain and your signal will be worse.
My location is Union to the east
Palmetto 800 Site: Greenville County Simulcast
Palmetto 800 Site: Greenville County Simulcast Details
www.radioreference.com
And I am in West Tennessee. We know the town not TV FM Radio Cell Towers and last but not least 2way Towers. You know your 8 mile circle better than us.
Trial and error...That's the nature of the hobby
One FM station. VHF tower and a 800 mhz tower don't know about cell probably a few I have to research that
Then you be asking for more trouble with high gain antennas and preamps.
Like I told you in other post learn about ham radio and make friends with locals in your area ham radio club. They live near you and can give you the best advice.
You need a local Elmer.
Like I told you in other post learn about ham radio and make friends with locals in your area ham radio club. They live near you and can give you the best advice.
You need a local Elmer.
What you think I should try at first a omni or yagi and what gain to start
Would you get 5,8 or 11 dbi
G7RUX
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If you can live with the size and the antenna is mounted at a decent height in clear air then go for the highest gain you can manage.
The most I can get is 11 dbi it's 90 inches
Ubbe
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A directional yagi antenna will work as a filter in itself, not picking up so much from other directions, lowering the interference level. There are even low noise yagis that are designed to have as minimal side lobs as possible to not pick up interference from your own building below and from neighbors in other directions.
I have tested and tried antenna amplifiers and the PGA103+ type works really well handling a strong RF environment and are not expansive. I know that prcguy had to use an expensive low gain and high 3dB noise amp that could withstand something like 1watt at its input and still not overload, but he had an extremely high interference level from transmitters very close by and also his own HAM transmit gear.
It is dependent of your receivers capability and the additional attenuation needed to do to the signal when using an amplifier and has to be tested at the exact location.
/Ubbe
I have tested and tried antenna amplifiers and the PGA103+ type works really well handling a strong RF environment and are not expansive. I know that prcguy had to use an expensive low gain and high 3dB noise amp that could withstand something like 1watt at its input and still not overload, but he had an extremely high interference level from transmitters very close by and also his own HAM transmit gear.
It is dependent of your receivers capability and the additional attenuation needed to do to the signal when using an amplifier and has to be tested at the exact location.
/Ubbe
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