Ham Antenna Mount Question

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RainierandTacos

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Ok so I got the antenna, coax and a fender mount on order. (5 dollars. Why not.) Is the fender mount going to require paint removal or will drilling it in take care of grounding? Also, does anyone have any recommendations for a fairly inexpensive SWR meter? I really don't care about toasting a 20 dollar baofeng but I'd like to do the mobile install as right as I can manage.
 

Sparksalot

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Ok so I got the antenna, coax and a fender mount on order. (5 dollars. Why not.) Is the fender mount going to require paint removal or will drilling it in take care of grounding? Also, does anyone have any recommendations for a fairly inexpensive SWR meter? I really don't care about toasting a 20 dollar baofeng but I'd like to do the mobile install as right as I can manage.
The drilled holes should give enough metal. I’ve done that on several vehicles.
 
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RainierandTacos

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I use a Surecom meter. It gives you a lot of info including SWR and power output.

I've looked at that one, was a little leery of the mixed reviews but I may end up pulling the trigger on it.

The drilled holes should give enough metal. I’ve done that on several vehicles.
Awesome, that's good to know. Thank you.
 

Ratthew

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That doesn't look like a good tie into the vehicle body for a good ground. I would be leery of it. Plus you'll need to remove all the paint from both your antenna mount and ditch light bracket at the contact points to make sure you have good RF continuity.
Will this be fine for a GMRS radio? I literally bought the same ditch light bracket mount (and a little "ghost" antenna to go with it) directly from Midland's website, and they feature a very similar picture. I assumed (maybe mistakenly) that if they sell one for the radio, the setup should work fine! But of course different bands.


The Rago mount would work fine with a 1/2 wave 2m antenna as it doesn't require a ground plane, however for other antennas that do you would have to remove much of the powder coating from the antenna bracket and the ditch light bracket in multiple places.

You could also go with a fender mount instead of the ditch light or hood lip mount for a better ground.

The generic L brackets are much cheaper.
Does GMRS have the same "grounding" plane issue that HAM antenna's have? I am studying for my HAM license now, so was hoping i could just use the same setup for HAM (maybe mount a second bracket on the LEFT side ditch, with the GMRS on the RIGHT side ditch. SO much to learn, thanks guys!
 

Prerunner1982

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Does GMRS have the same "grounding" plane issue that HAM antenna's have? I am studying for my HAM license now, so was hoping i could just use the same setup for HAM (maybe mount a second bracket on the LEFT side ditch, with the GMRS on the RIGHT side ditch. SO much to learn, thanks guys!
It affects all types of radio services/frequencies.
 
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slomatt

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I just did a similar install on my 2nd gen Tacoma, except that the antenna is mounted directly to the "ditch light" bracket. On my install I used an NMO mount and ground off some paint where the NMO clamp touches the bracket and also where the bolts contact the bracket to hold it to the hood. I re-sealed both places afterwards to prevent rust. I then used a multimeter and confirmed very low resistance (tenths of an ohm) between the antenna and the negative battery terminal. And yes, the concern is not with a low resistance connection to the battery and is instead in establishing a good ground plane, but I figure if the ground connection was good then it means the connection to the chassis and hood is solid. I also bought an NMO to 3/8" stud adapter so I can put a CB antenna on the same mount and was able to achieve a SWR of below 1.5.



Ultimately I will likely put an NMO mount on the roof where the satellite radio antenna is currently since I don't like the idea of transmitting at 50w so close to my face. But, this hood mounted setup is working great for now and I usually run lower power anyway.
 

RainierandTacos

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Got the bracket mounted today and test fit the antenna. Things look pretty good for the moment. Once I find my multimeter and soldering iron I will get the cable routed and connector mounted. Looking at where its mounted, I'm curious what kind of power people with similar setups are running? That seems a little close for me to be running a full 50 watts. Is that something I should be concerned with?
 

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Sparksalot

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I just did a similar install on my 2nd gen Tacoma, except that the antenna is mounted directly to the "ditch light" bracket. On my install I used an NMO mount and ground off some paint where the NMO clamp touches the bracket and also where the bolts contact the bracket to hold it to the hood. I re-sealed both places afterwards to prevent rust. I then used a multimeter and confirmed very low resistance (tenths of an ohm) between the antenna and the negative battery terminal. And yes, the concern is not with a low resistance connection to the battery and is instead in establishing a good ground plane, but I figure if the ground connection was good then it means the connection to the chassis and hood is solid. I also bought an NMO to 3/8" stud adapter so I can put a CB antenna on the same mount and was able to achieve a SWR of below 1.5.



Ultimately I will likely put an NMO mount on the roof where the satellite radio antenna is currently since I don't like the idea of transmitting at 50w so close to my face. But, this hood mounted setup is working great for now and I usually run lower power anyway.
I've had that kind of arrangement in the past. If you think about it, you transmit very little compared to listening time. My current rig has three roof mounted antennas, but I'd consider a cowl mount again if I had a roof rack.
 

Stormcrow

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Sorry, I realize I’m joining this conversation a bit late. I use the Rago ham mount for the hood (same thing as their ditch light mount, only with a 3/4” hole for a NMO mount). I have a 1 ft braided grounding cable running from the mount & hood bolts to a body bolt in the engine compartment. My tx/rx is just fine and the professional radio installer that helped me (I think he’s probably been a ham longer than I’ve been alive) didn’t see a problem with that location.

D958F725-8E8C-458B-B44C-F4513EDC74EF.jpeg
 

Dilldog

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Im running a similar antenna mount. I actually scavenged an odometer mount for an HD trailer hub out of the scrap bin at work, then used some sheet metal screws to mount that to my fender, then mounted the antenna to the mount. I made sure there was a good ground by removing paint where fasteners contacted the mount. I did use some blue loc tite on the sheet metal screws and I coated anywhere I had removed paint with corrosion inhibitor (get the brownish stuff marketed by Truck Light) after installation. I have no problem running 50W with this set up.