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Best Coax Cable

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Nashua NH
#1
I need the best coax cable money can buy to run a scanner coax cable to 3 antennas outside of a communications building.

Approximate run: 300 feet
UHF / VHF / 800 Mhz, P25, etc

We already have a pipe that runs direct to the area where the cable will be needed.

Price is really not an option. But if you could list the top 3 cables, it would help me very much!

Jeff
 
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#3
I need the best coax cable money can buy to run a scanner coax cable to 3 antennas outside of a communications building.

Approximate run: 300 feet
UHF / VHF / 800 Mhz, P25, etc

We already have a pipe that runs direct to the area where the cable will be needed.

Price is really not an option. But if you could list the top 3 cables, it would help me very much!

Jeff
So you need the "best coax cable money can buy" and "Price is really not an option" than you should really consider nothing but what is used by stations with those tall towers and really need the lowest loss where cost is really a minimal factor, rigid feedline, probably the 6 1/8" size. Sure, it's expensive. Sure it's hard to install (you'll only do that once though so who really cares about that anyway). Sure it's heavy (but the tower can easily be designed to handle that). You'll probably never beat the loss figures (0.15 dB of loss at 800 MHz per 100 feet - and note the decimal point, that's less than a third of a dB per 200 feet in length!!!).

http://www.dielectric.com/wp-content/uploads/2015/11/Transmission_Line_Catalog.pdf

Just remember to install those spring hangers so you don't damage the coax as the temp changes. Copper and steel have different temperature expansion coefficients so you'll need to allow the springs to keep the steel (or aluminum) tower from stretching or contracting the rigid coax as the temp changes!

And you can use that high loss Andrew stuff suggested above for your jumpers between the rigid coax and your antenna or radios.
 
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Joined
Feb 11, 2009
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#4
You are limited by the diameter of the pipe and how many bends it has to make and what bend radius would be encountered

Pulling 300 feet of flexible rg8 type coax would be difficult enough let alone trying to pull heliax through multiple bends inside a pipe

And if you are talking about pulling 3 runs, it better be a huge pipe
 
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Point Nemo.
#6
I need the best coax cable money can buy to run a scanner coax cable to 3 antennas outside of a communications building.

Approximate run: 300 feet
UHF / VHF / 800 Mhz, P25, etc

We already have a pipe that runs direct to the area where the cable will be needed.

Price is really not an option. But if you could list the top 3 cables, it would help me very much!

Jeff
As others have said "Best" can mean a lot of things, and the "best money can buy" statement suggests that maybe you are not aware of actual costs of some of this stuff.

All that aside, MOTEX nailed it when he mentioned the size of the existing conduit that gets you outside.

Also, the exact type of usage would help us make a suggestion. Is this receive only, or will there be any transmitting?
What kind of radio are you connecting to?
What kind of antenna? Gain?
How strong/weak is the signal you are trying to receive?

Coaxial cable is very important to you system, but the "money is no object" approach can lead to some pretty weird decisions being made. While you could certainly go with some large Heliax cable, that actually may not be the best solution.

Also, the path that the cable needs to follow to reach the antenna matters a lot.
You cannot just run any type of cable you want through a commercial building. At minimum you need a riser rated cable, but you may need to step up to a plenum rated cable depending on the route it takes. This isn't like running some cheap coaxial cable through your attic.

Low loss cable capable of getting an 800MHz signal to/from your antenna with any useful amount of signal left over on the ends requires some large coaxial cable. That alone creates some issues with how it's routed. It doesn't like to make sharp turns. It's heavy, so it needs proper support. Getting it pulled into an existing building is going to be a really big job requiring a lot of people and equipment.

As mentioned by others, a preamplifier might be an option, but you are still going to need some good cable.

A better approach is to put the radio closer to the antenna and remote the controls/audio using cheaper means down to where you need it.

If money really is no object, then running 300 feet of coaxial cable to the roof isn't the right approach. A networked receiver might be a much better and cheaper solution.

I think you need to fill in some blanks for us if you want a useful answer.
 
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Lowestoft - UK
#7
The real killer here is simply one feature - 300ft! If we ignore the price totally, then this is the equivalent of feeding upwards to a VERY high tower. 800MHz as a target frequency is also going to be a pig.

My favourite cable LDF4-50 - the best balance of weight, performance and bendbility still loses over 6dB at 900MHz - in practical terms, you will lose 75% of the signal in the feeder. Loss is of course much less as soon as you drop in frequency. If the 800MHz antenna has some gain - maybe this will counteract the loss, but a pre-amp designed for mast head use is pretty important, just to up the signal so the loss in the cable is counteracted. In the UK, 3 100m lengths of this cable is going to be around £2000, but inserting just one length in a conduit will be a serious job, even with pull throughs.
 
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Location
Texas
#9
The real killer here is simply one feature - 300ft! If we ignore the price totally, then this is the equivalent of feeding upwards to a VERY high tower. 800MHz as a target frequency is also going to be a pig.

My favourite cable LDF4-50 - the best balance of weight, performance and bendbility still loses over 6dB at 900MHz - in practical terms, you will lose 75% of the signal in the feeder. Loss is of course much less as soon as you drop in frequency. If the 800MHz antenna has some gain - maybe this will counteract the loss, but a pre-amp designed for mast head use is pretty important, just to up the signal so the loss in the cable is counteracted. In the UK, 3 100m lengths of this cable is going to be around £2000, but inserting just one length in a conduit will be a serious job, even with pull throughs.
Let me translate that to the units of measure we use on this side of the Atlantic.

LDF4-50A = Andrews (ComScope) 1/2" Heliax. MSRP is $3.18 a foot so Hutton/Tessco price will be around $2.30 a foot for most.

300 ft is average tower height here in the US for traditional two-way applications. Just thinking of stuff I've worked on this year, most sheriff's offices run 300 feet towers, Motorola likes to engineer for 300 foot towers for trunking systems, we've got customers anywhere from 40 ft to 1500 ft right now.
 
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Lowestoft - UK
#10
I remember reading a Clive Cussler novel in the early two thousands where they did all the measurements in both Imperial and Metric - and as it was so long ago, I assumed people in the US would be used to metric by now - 3 x 300 x $2.30 is $2070 plus the connectors - so assuming your tax is about the same - your price is the same as our price

as in 3 x100m at our pounds version converted to Dollars. No need to convert it - it's the same! I figured everyone would know that 100m - 300ft- sorry! Here, everyone does metric and feet and inches.
 
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Location
Texas
#11
I remember reading a Clive Cussler novel in the early two thousands where they did all the measurements in both Imperial and Metric - and as it was so long ago, I assumed people in the US would be used to metric by now - 3 x 300 x $2.30 is $2070 plus the connectors - so assuming your tax is about the same - your price is the same as our price

as in 3 x100m at our pounds version converted to Dollars. No need to convert it - it's the same! I figured everyone would know that 100m - 300ft- sorry! Here, everyone does metric and feet and inches.
It really depends on how old you are. Everything here is still priced per foot so not everyone is used to doing the the 1.09 yards to meter conversion. That used to be a pet peeve of mine when in school...convert it all to SI then go from there and convert it back when done (if there was time).
 
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#12
I assumed people in the US would be used to metric by now
Yeah, you'd think we'd be using metric by now.
I was in school in the 70's when there was a big push to adopt the metric system. We had to learn both, and I'm comfortable with both systems.
I don't understand the knee jerk reaction that some Americans have to the metric system. I think most of it is pure misunderstanding. So much paranoia here sometimes.

The US Military uses metric, and quite successfully. At work a lot of our stuff is metric.

Eventually, generations will change and the SI system will take over.
 

JamesO

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#13
Not knowing all the end result requirements, this is a hard question to answer. But this being said, 300 feet is a problem at any frequency for receive performance.

Believe it or not, I bet I could get better results and save a bunch of time and money using RG-6 cable, a decent Pre-Amp and broadcast filter if necessary along with a Tilt Compensator or 2 and this all can be DC phantom fed with a Bias T. If you do not want to deal with a Bias T configuration, run an extra RG6 cable and use this for a DC feet to the antenna location, I use coax all the time as DC power wire.

Suggest you read this thread -
https://forums.radioreference.com/s...mp-10-off-december-other-useful-rx-items.html

Sure you can spend a bunch of money, but a bunch of money will not always get you want you may want to need.

I have a similar set up at the house with about 150 feet of RG6 and it works VERY well. Antenna is currently in the attic, soon to move outside, but even this configuration is better than my handheld with a decent antenna outside.

It really is based on how robust this system needs to be and are there any near field transmitters that could damage the Pre-Amp or need to be filtered out due to the high input power at the antenna feed location.
 
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