Ground Radials for a Mobile Antenna

[CaptKalbo]

I bought a ground radial adapter off eBay. It looked like it wad made to screw in on the ground side of the antenna lug. I received it, today and to my surprise, it attaches between the antenna and the antenna lug. This would place it on the wrong side of the antenna, right? This is the listing. I have one in my hand, though. I also have a NanoVNA to test it with. I'm actually trying to use a mobile antenna for a base. That's why I need the radials. Has anyone else tried one?
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[The DB]

These devices, even if on the right side of the feed point, do not act like radials. They aren't anywhere near long enough. They need to be in the order of 9 feet long give or take to be radials for a mobile antenna.


The DB

[CaptKalbo]

These devices, even if on the right side of the feed point, do not act like radials. They aren't anywhere near long enough. They need to be in the order of 9 feet long give or take to be radials for a mobile antenna.


The DB

Yes, I agree with the length limitation. But I was wondering if anyone has tried using a coiled fiberglass antenna. I think they were trying to make it look that way, by placing the rubber covers on the tips of the radials. I have found a better radial system on Walcott Radio's web site. Their radials are 4 foot long and appear to be fiberglass whips.

[MDYoungblood]

That thing you bought, all I ever saw them do is add an inch of length to the antenna. Ground plane is part of the shield side of the antenna system. What is the antenna you are making into the base? A cheap ground plane would be 3 or 4 wires about 8' 6" to 9' sloped at a 45° angle, could even be more if you wanted.

3's

Greg

[CaptKalbo]

That thing you bought, all I ever saw them do is add an inch of length to the antenna. Ground plane is part of the shield side of the antenna system. What is the antenna you are making into the base? A cheap ground plane would be 3 or 4 wires about 8' 6" to 9' sloped at a 45° angle, could even be more if you wanted.

3's

Greg

I've got several Wilson 2000s. Right now, I've got one mounted on a flag pole with an inverted "Dish Network" Dish for a ground plane. It actually has an excellent SWR....But, on 29.620Mhz. I'm going to replace the 10" shaft with a 22", so I can trim the stinger into the right band for CB. It looks like it came from a junk pile, because I made it from junk. I hate to throw anything out, really.

[MDYoungblood]

Well it is in the ballpark, just a tad short. Before changing the shaft try adding a couple wires (3 or 4) to the dish to give it a little more plane, they don't need to be sticking straight out. Can also try a dirty choke in the coax about 8 1/2 to 9ft below the connection, (5 wraps about 4 1/2" diameter). Experimenting is where the fun comes in.

3's

Greg

[CaptKalbo]

Well it is in the ballpark, just a tad short. Before changing the shaft try adding a couple wires (3 or 4) to the dish to give it a little more plane, they don't need to be sticking straight out. Can also try a dirty choke in the coax about 8 1/2 to 9ft below the connection, (5 wraps about 4 1/2" diameter). Experimenting is where the fun comes in.

3's

Greg

That's a good idea. I've got about 45' of Transflex RG8x. Maybe not the best for a base, but I already have a bunch of it and it will coil up that small with ease. I haven't put connectors on, yet, but I have pack and a soldering station. I'm off tomorrow, so I'll tinker. I'm also learning to use my NanaVNA. It's handy for SWR.

[The DB]

Yes, I agree with the length limitation. But I was wondering if anyone has tried using a coiled fiberglass antenna. I think they were trying to make it look that way, by placing the rubber covers on the tips of the radials. I have found a better radial system on Walcott Radio's web site. Their radials are 4 foot long and appear to be fiberglass whips.

Using 4 foot long mobile antennas for radials does work, its the electrical length, which in that case is longer than the physical length, that matters. I would be cautious as using radials shortened to much in that they will greatly limit the bandwidth of the antenna. There was a member of this forum that experimented with such, a predator for the vertical and I believe four firestik antennas was the radials. He said it worked pretty good. The radials (and the ground part of the coax) were isolated from the vehicle. As I recall, he had to have the radials something like 4 to 6 inches above the vehicle in order to tune it.

His posts were lost during a forum crash a while back, and I haven't seen him post in a while...


The DB

[nosaj]

Seems more like a tophat than anything else.
nosaj
N1EBC

[jessejamesdallas]

I bought a ground radial adapter off eBay. It looked like it wad made to screw in on the ground side of the antenna lug. I received it, today and to my surprise, it attaches between the antenna and the antenna lug. This would place it on the wrong side of the antenna, right? This is the listing. I have one in my hand, though. I also have a NanoVNA to test it with. I'm actually trying to use a mobile antenna for a base. That's why I need the radials. Has anyone else tried one?
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Don't throw it away!

Remove the rubber caps off the ends of the radials...

Use it to throw at neighbors dog when you catch it taking a crap in your yard...