Questions tagged [mobile]

Mobile operations (car, motorcycle, boat or other vehicle)

Filter by
Sorted by
Tagged with
13 votes
2 answers
5k views

Is there an optimum Antenna Feedline Length for mobile installations?

I bought a ham radio antenna mounting kit for my car that includes ~16' of coax. One end has a trunk lip NMO antenna mount, the other end has a re-solderable PL-259. I asked the sales person if it is ...
BenSwayne's user avatar
  • 681
9 votes
7 answers
16k views

When and why does the size of a ground plane or radials matter?

Consider these three cases: My understanding is that when building or installing an antenna designed to operate over a ground plane (e.g. a quarter-wave vertical), the size of the ground plane does ...
Kevin Reid AG6YO's user avatar
  • 24.5k
6 votes
3 answers
13k views

How do I power my radio in a vehicle mobile install?

I want to install a 30W mobile UHF radio in my car. I already have an antenna and mounting bracket - but how do I get power to this radio? It has an SAE bullet connector on the back - do I just need a ...
Dan KD2EE's user avatar
  • 3,966
19 votes
3 answers
34k views

How does a mag mount antenna achieve a ground plane?

I've been thinking for some time about magnet mount mobile antennas and wondering how they establish their ground plane. Consider that many mag mount antennas have some kind of protective coating on ...
Peter KB1AVL's user avatar
11 votes
5 answers
33k views

Should I ground my radio to the chassis or battery for a mobile install?

From what I've seen, there are generally two ways to power a mobile radio: Positive lead to battery, negative lead grounded to chassis Both positive and negative leads to battery I know that ...
Ben's user avatar
  • 213
7 votes
4 answers
1k views

How would you get an "I'm alive" message to family in another state using amateur radio?

I'm researching options for getting an "I'm alive" message during a disaster response out to family in another state that aren't HAMs. There are likely to be a lot of possible answers that are art ...
Matthew Wetmore's user avatar
6 votes
3 answers
3k views

antenna in the rain

What kind of changes can be expected in the behavior (resonance, SWR, etc.) of a mobile vertical HF antenna between dry conditions and wet rainy weather? (assume a coax feed-line and low SWR in dry ...
hotpaw2's user avatar
  • 13.3k
6 votes
2 answers
5k views

What are some good options for covert dual band vehicle antennas?

Would like to have a 50W mobile in my SUV, but I'm not allowed to have a big whip on the outside. What 2m/70cm dual band antennas are available that don't say, "Ham Radio Operator"? Are there three ...
Adam Davis's user avatar
  • 12.1k
5 votes
2 answers
265 views

Amateur Radio for a Nomad [duplicate]

I got my amateur license back in the early '80s, primarily for putting it on my resume for an electronics job. Never used it outside of developing my Morse code speed, and once I got my Advanced Class ...
KiloVoltaire's user avatar
5 votes
1 answer
2k views

How to calculate or estimate surface area of required ground plane for a mobile antenna?

I don't have conditions for installation of a fixed 2 m/70 cm antenna at home, so I'm thinking of using a mobile magnetically mounted antenna on a conductive plate instead. So my question is: What ...
AndrejaKo's user avatar
  • 2,893
4 votes
7 answers
4k views

Slot antenna for 2 meter mobile

My primary vehicle is a Smart car, with a roof that's a piece of plastic(100% moon roof). Not the most awesome of cars to use for grounds. I'm building a bumper mounted antenna tower, EMT with some ...
Omagasohe's user avatar
4 votes
2 answers
4k views

Does effective grounding of mobile (vehicle) antenna mounts address common-mode currents?

While researching how best to install my mobile amateur radio in my car, I didn't understand if there was optimum Antenna Feedline Length for mobile installations? Understanding that this is caused ...
BenSwayne's user avatar
  • 681
1 vote
2 answers
1k views

GMRS not transmitting within a half mile

I recently got my GMRS license from the FCC, and I wanted to try out a couple radios for hiking and emergency communication. I have two tenway UV-5R pro radios (these do have an FCC ID) that are set ...
user16052's user avatar