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Brand new amateur radio license holder, and I (still) know next to nothing. As I posted in my previous thread, I recently got my mobile radio: Anytone D578UVIIIPlus. The base station accessory bundle I also got, came with this vertical antenna: AnyTone Tri-band Mobile DMR Antenna.

I'm interested in setting up that vertical antenna in the attic above where my radio will be in ground-floor office. I live in a rambler home with an attic and basement. My office is on the west side of our home, and I have a west-facing window.

My initial hope and intent was to set up that vertical antenna in my attic attached to its mag mount without any additional modification and without having to ground it and be able to safely transmit. My understanding is that I wouldn't need to ground the antenna within the attic as the home would protect it from lightning. I'm new and there might be something I'm not considering.

Can I safely set up and transmit using that vertical antenna in my attic without any additional modification?

My previous mystery antenna thread has some rudimentary pictures of my attic if that's helpful.

chicks
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Jared
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Grounding is not necessary, but it is probably a good idea to add 3 or 4 radial lines. Just cut a wire (anything 18 AWG or thicker, solid or stranded, any scrap wires would do) to about 50cm, connect them to the feedpoint ground (coax braid). Those lines should be placed at rather even spread angles and horizontal to the ground. You might also want to add a few shorter radials (17cm long) for the 70cm band. That antenna is 112cm long, so it is probably a 1/2 wavelength endfed on 2m, which is supposed to require no radial (the coax braid alone might be adequate). But the antenna should perform more stably/reliably with some radials. (The antenna is made for vehicle use where the feedpoint is grounded to vehicle chassis at the mount, so it is best to create an environment electrically similar to that.)

Ryuji AB1WX
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Another way to mount the antenna is on a metal plate of some type. I have seen pizza pans used for this. As your antenna is not a magnetic mount, drill a hole in the center of the pan or plate to attach the antenna. The metal plate or pan takes the place of the metal body of your vehicle.

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    That would work for 1.25m and up but the biggest pizza pan I've heard of is still 16-inch diameter, a bit too small for the 2m ops and hungry hams. – Ryuji AB1WX Nov 12 '24 at 18:24
  • Thank you for your comment. Yeah, the base station bundle was supposed to include a magnetic mount for the antenna, but that wasn't included in what they shipped me for some reason. I've reached out to BridgeCom to ask them about it. They did include some kind of trunk lip mount, I think. – Jared Nov 12 '24 at 23:10
  • I believe I have read for this antenna, a magnetic mount is not recommended. it is too heavy and they were worried that it might fall off a vehicle while it was being driven. –  Nov 13 '24 at 14:05
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    yes a pizza pan is not the large enough to be an ideal ground plane, but it is large enough to function. Most hams are running some type of compromised antenna. I have a 2 meter antenna with a magnetic mount sitting on 12 by 12 inch metal sheet on top of a wooden bookcase in my ham shack. it is better than the rubber duckie antenna on the hand held. –  Nov 13 '24 at 14:19