Equipment Requirements for Mobile Install

Peter1154

Newbie
Joined
Jul 31, 2024
Messages
1
New ham looking into getting a dual-band mobile for my '05 4runner. As of now, I'm leaning toward the ICOM 2730a and Larsen nmo2/70b. Main question is do I need some sort of SWR meter/antenna analyzer to measure SWR before transmitting on a mobile install?

On another note, any suggestions of non-hole mounting methods? Unfortunately I am unable to drill the hole. I know there are pros and cons to each method, just looking for personal experiences or advice.

Thanks in advance.
 

mmckenna

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Jul 27, 2005
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United States
Usually the antennas are tuned pretty close out of the bag. As long as you install it properly, you'll probably find that the SWR is acceptable. But, it's a good idea to check it after install, just to rule out any issues. You don't need to spend money on an expensive meter or something like a nano-VNA for a one off installation with a commercially made antenna.

Permanent mount antenna will give you better performance. Non-drilled mounts can create issues with tuning, directionality, and performance. If drilling the hole is absolutely off the table, we'd need to know what your other options are.

If you have some sort of overlander type rack on the roof, there are mounts that can work with that, but not all mounts are good, and not all mounting locations are good. Plus, you have to deal with cable routing.

Many take the short cut route of doing a fender bracket. That allows easier(ish) cable routing through the firewall to the radio, but having the antenna too close to the cab can cause reflections. Offset mounting on the fender will make it directional. Also, having the coax too close to the engine bay/ignition can result in some issues.

Gotta pick your compromise, what's more important to you? Easy installation? Better performance? Low clearance? Your skill level?
 

ladn

Explorer of the Frequency Spectrum
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Oct 25, 2008
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1,457
Location
Southern California and sometimes Owens Valley
New ham looking into getting a dual-band mobile for my '05 4runner. As of now, I'm leaning toward the ICOM 2730a and Larsen nmo2/70b. Main question is do I need some sort of SWR meter/antenna analyzer to measure SWR before transmitting on a mobile install?

On another note, any suggestions of non-hole mounting methods? Unfortunately I am unable to drill the hole. I know there are pros and cons to each method, just looking for personal experiences or advice.
Welcome to RR.

I have a 2730A in my 2018 4Runner. In town, I use an 18" VHF whip on an NMO mount. Out in the backcouontry I use the Larsen NMO 2/70.

You won't need an SWR meter or analyzer. The Larsen antenna is good to go from the factory for ham frequencies. It will also be fine for RX on any frequency within the range of the radio, but if you are planning on transmitting "elsewhere" on high power, you'll want to check the SWR as the NMO 2/70 has a somewhat narrow bandwidth. Also, if your Larsen has the open coil in the middle of the antenna, you might consider covering it using heat shrink tubing. The coil is a branch catcher!

If you haven't done so already, I strongly recommend purchasing the RT Systems programming software with cable.
 

nokones

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Premium Subscriber
Joined
Feb 19, 2011
Messages
617
Location
Sun City West, AZ
A Lip NMO attached to the rear edge of your hood might fit your application. If you have a Roof Rack and depending on the style of that rack I may have another solution, but it will require that you run a cable up to the rack.

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