Using Portable antenna on Mobile Radio

[Binger511]

I understand that it may not be ideal, however its what I'm working with/experimenting with at the moment. Right now I am using a Kenwood TK-8180 with a KRA-27 UHF portable antenna inline to a "PL259 Male -->SMA Male" attached to the mounting bracket. I very rarely ever transmit, and when I do it is on low power and only for a few seconds. (Basically just a scanner at the moment). I got some confidence that it would work when I saw a Kenwood Kairos DMR repeater video where they have the same basic setup with a similar setup as seen below:


I am open to criticism/tips to see if there is anything I can be doing that could make the setup better. Or if what I am doing should be stopped immediately due to spontaneous combustion of said radio. My setup:

 

[CommsTruck]

turn down the power low and get a 90 degree adaptor it will be fine.

 

[spacellamaman]

personally i would square up the tape ends a bit.

make it look more professional.

neatness counts ya know.

 

[2154]

Would it be possible to just get a short cable'd NMO magnetic mount and a stubby NMO antenna on it? I'm not sure how the ground plane would be but you wouldn't have to worry as much about the tx power when you do transmit-and probably have better reception.

 

[alcahuete]

You will have MUCH better luck doing what @2154 says. Take a magnet mount with a 1/4 wave NMO and stick it on top of your power supply. Still a compromise, but it will perform much better.

 

[mmckenna]

I am open to criticism/tips to see if there is anything I can be doing that could make the setup better. Or if what I am doing should be stopped immediately due to spontaneous combustion of said radio. My setup:

It's not going to damage your radio. These radios have a circuit in them that sense high SWR and will back off the power so as not to cause any damage. Even then, high SWR doesn't result in miniature mushroom clouds appearing over your radio, as some in the CB world think will happen.

It might work 'well enough' for what you need, and it's fine. But you'll get much better performance if you do a magnetic mount on top of a ground plane, like a file cabinet or something. It'll receive better and transmit better.
Or better yet, get the antenna outside.

It's often done at trade shows, but they'll keep the power low.

 

[bharvey2]

I have a similar setup with a UHF radio that I use for an Allstar node I set up at home inside my garage. I use a mobile radio set to low power and I made a quarter wave antenna out of an SO239 connector and some brass rod for the radiator and radials. It's tuned to the frequency I use on my node but as it's a quarter wave antenna, I imagine I have some latitude with it in the 70cm ham band. If I weren't concerned with zapping myself with a lot of RF energy, I'd have no worries about running it at full power. It looks something like this:

 

[Binger511]

personally i would square up the tape ends a bit.

make it look more professional.

neatness counts ya know.

Haha, the flash from my phone makes it look rather scungy. Nothing that some more dollar tree electrical tape can't fix (;

I have a similar setup with a UHF radio that I use for an Allstar node I set up at home inside my garage. I use a mobile radio set to low power and I made a quarter wave antenna out of an SO239 connector and some brass rod for the radiator and radials. It's tuned to the frequency I use on my node but as it's a quarter wave antenna, I imagine I have some latitude with it in the 70cm ham band. If I weren't concerned with zapping myself with a lot of RF energy, I'd have no worries about running it at full power. It looks something like this:

Now if I had the skills to do something like that, that's what I'd do. I'm curious though, do you run a right angle connector inline between the radio and antenna or just have it horizontal?

 

[bharvey2]

Haha, the flash from my phone makes it look rather scungy. Nothing that some more dollar tree electrical tape can't fix (;



Now if I had the skills to do something like that, that's what I'd do. I'm curious though, do you run a right angle connector inline between the radio and antenna or just have it horizontal?

Don't sell yourself short. The radio hobby is very much a DIY endeavor. Lots of people MacGyver their own equipment.

It really isn't too hard to make. Soldering the radial is probably the toughest part. The radials are bent into a loop with needle nose pliers and screws hold it to the SO259 connector through the pre-existing mounting holes. As I recall, I had a piece of scrap metal that I made a bracket out of that matches the mounting holes of the SO259. I also drilled a large hole through it so the PL259 connector would screw on to the SO239. THe bracket in turn, mounts to a board on the wall. My length of coax has standard PL259 ends on it. No right angle connector was needed.

If looks aren't important, you could do the same thing and tape or zip tie a stick to the coax as it runs to the SO239. That antenna only weighs a few ounces. Also note that bare copper wire was used in the antenna in the photo. It can be bent pretty easily with pliers. Other than the SO239 connector, all of the parts are available at a hardware store.