My antenna setup, feedback wanted (photo attached)

[nezza]

Good afternoon,

I have just finished putting my antennas up and looking for some feedback in relation to positioning. I would like to know if the antennas are too close to each other or not. This set up is purely for receive only and from what I've noticed the antennas are not interfering with each other but would like some professional advice. The top antenna is a UHF approximately 470 MHz. Next is a nine element yagi followed by a side mounted dipole. Thank you.


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[mmckenna]

Looks OK to me.
For receive only, not reason they should interfere with each other.

If all your coaxial cable is secure and waterproofed, you should be good to go.

 

[KC4YIN]

And GROUNDING! What did you do for grounding. That top uhf makes a great lightning magnet.

 

[prcguy]

Looks ok to me also. I would however bring the coax from the Yagi straight back to the mast and down where you have it exiting close to the reflector and heading down at an angle.

You don't really need the big service loops in the coax, just leave a small one as the coax comes off each antenna, then gently attach the coax to the mast at that point with Ty-Raps or something that will not crush or distort the cable. I like to immobilize any coax connections with Ty-Raps either side of the connection where you have the pigtail off the antenna and the connection flapping in the wind.

Looking at the dipole, if you were to leave the same service loop in the pigtail and Ty-Rap the coax right above the first coax connection, then loose the big service loop, then Ty-Rap as needed down the mast I would be happier. Do that for all antennas, running all the coax really straight and parallel so it doesn't look messy as the coax heads over the peak of the roof. And you might bend the coax away from the viewer on the roof for a few feet as a service loop in case you need to redo something in the future.

If I were to install something like this for a customer I would be looking for them to say "wow" when the job is done and you have to pay attention to small details to raise the wow factor.
[rcguy

 

[spongella]

Nice neat, clean job, and great idea to have looped some extra coax for wiggle room when doing maintenance.

Side mounted dipole is for what service?

 

[Ubbe]

And GROUNDING! What did you do for grounding. That top uhf makes a great lightning magnet.

It will for sure be a lightning magnet if you ground it.

I know one radio site that where extreamly grounded and each lightening season it picked up direct hits that created massive EMP and some equipment always failed. After some years they got tire of it and removed all grounding and isolated the hut from ground and have never had any direct hits since and all equipment are at the same potential and didn't got damage by near lightning strikes.

So, don't try to lead the lightning strikes to your antenna, try to keep it away. If you get a direct hit nothing will help anyhow.

/Ubbe

 

[mmckenna]

It will for sure be a lightning magnet if you ground it.

That's not the way it works.

Grounding is giving the energy a path to where it want's to go to. Lots of towers take directly lightning strikes and the equipment keeps working just fine. That's because it's been properly grounded and protected.

Not grounding will do nothing to protect you. The energy has traveled thousands of feet through the air, a house, piece of plastic, electrical tape, coaxial cable jacket, etc. isn't going to stop it.
Properly getting that energy where it want's to go is what will protect you.

 

[lmrtek]

Actually pretty impressive

Spacing is fine and the coax loops provide lightning strike impedance so kudos there too

A very low impedance ground wire is a must with a fiberglass antenna top mounted and be sure and install polyphasers as well

 

[nezza]

Thank you all for your feedback, much appreciated and helpful.

In relation to the coax coming off the yagi, the fact it's not running along the horizontal pole and just hanging down, would that cause issues/interference to the reflector?

Also, I have no intention of grounding the mast. Does grounding the mast improve RX reception at all?

My biggest issue was spacing as I have heard antennas too close to each other can cause issues to each other.

This is my first real attempt at an antenna roof setup.

Thanks again!

 

[mmckenna]

In relation to the coax coming off the yagi, the fact it's not running along the horizontal pole and just hanging down, would that cause issues/interference to the reflector?

It can detune it and/or impact the directionality of it. For RX use, probably not an issue

Also, I have no intention of grounding the mast. Does grounding the mast improve RX reception at all?

Trouble with that is that it may already be grounded by way of the coaxial cable shield and through your radios. A direct lightning strike isn't the only risk. Nearby strikes and induce enough energy to damage the radios, start a fire, hurt someone, damage other electronics in your house. Even windy days can generate static electricity. That static electricity can certainly generate a lot of noise and can damage your radios.

Your radios, your antennas, your house, your choice. Just keep in mind there's a really good reason it's required under the National Electric Code.

My biggest issue was spacing as I have heard antennas too close to each other can cause issues to each other.

With transmitting, yes. With receiving, maybe, but it looks like yours are spaced out pretty well.

This is my first real attempt at an antenna roof setup.

Thanks again!

Looks like you did a pretty good job.