Rf noise

[M0GVZ]

Magmount or fixed mount?

 

[678 nh]

Magmount or fixed mount?

Ground straight to chassis

 

[678 nh]

Might want to try 6-10 snap on ferrite chokes at the antenna feedpoint. Use ones that fit snugly around the coax or they won't work correctly. There are a couple of eBay sellers that have good ones that do work. These are the ones I have and have used on a mobile install and they did work! Seller on EBay is henryradio. If you need them for larger coax just make sure they are the right mix for the frequency's being used. The ones I posted were ised on lmr240 at the feedpoint of a homemade dipole. Think I used about 12 of them total. Did the same exact thing on my mobile setup. Used 12 of the ones shown below. They worked well in that install as well. They also work well for wrapping around speaker and power wires. And also for mic cables. The smaller round ones sometimes are easier to work with on mic cables though. Ones like this work well for mic cables. It's attached below the mic itself.

Does the choke on the mic help audio out be a lil clearer. I deff wanna get some for my spark plug wires an on coax ..it looks lik my alternator is grounded to engine block then to batt. Then batt to inner fender.also see engine ground strap to fire wall.

 

[M0GVZ]

Ground straight to chassis

The clue is in your picture.

That bit of red wire does nothing for being a RF ground and the way the mount is construed you've effectively not got one. If you're OK with drilling holes then a Breedlove Ball mount in the rear quarter panel under the window on the side would be a better idea. One of these puppies

https://breedlovemounts.com/CB_antenna_ballmount.html

with one of their backplates.

https://breedlovemounts.com/Backing_plates.php

 

[678 nh]

The clue is in your picture.

That bit of red wire does nothing for being a RF ground and the way the mount is construed you've effectively not got one. If you're OK with drilling holes then a Breedlove Ball mount in the rear quarter panel under the window on the side would be a better idea. One of these puppies

https://breedlovemounts.com/CB_antenna_ballmount.html

with one of their backplates.

https://breedlovemounts.com/Backing_plates.php

Swr 1 to 1. Mount upside down in that pic but othr than that the 12 gauge wire is grounded to frame an mount bracket welded to body think thats gd..system works gd so gd im getting noise from engine so problem At engine. Prob. Been nit picking idk tx 4 reply mont been altered a bit so i can take a anothr pic latr.

 

[678 nh]

The tech at

The clue is in your picture.

That bit of red wire does nothing for being a RF ground and the way the mount is construed you've effectively not got one. If you're OK with drilling holes then a Breedlove Ball mount in the rear quarter panel under the window on the side would be a better idea. One of these puppies

https://breedlovemounts.com/CB_antenna_ballmount.html

with one of their backplates.

https://breedlovemounts.com/Backing_plates.php

Bells cb told me to

The clue is in your picture.

That bit of red wire does nothing for being a RF ground and the way the mount is construed you've effectively not got one. If you're OK with drilling holes then a Breedlove Ball mount in the rear quarter panel under the window on the side would be a better idea. One of these puppies

https://breedlovemounts.com/CB_antenna_ballmount.html

with one of their backplates.

https://breedlovemounts.com/Backing_plates.php

Also the tech at bells cb instructed me to ground mount to frame evan tho i told him my bracket is welded to the bodey so now i hav both just in case. I hav a ball mount i could try but i think id b going off track. Jeeps are noisey. My ? All alone has been y only in ssb i pick up spark plug chopper noise when engine is running but in am its barely noticeable. Is ssb more sensitive to receive? My jeep also has this morning a no bus code an gauges stop working idk weird

 

[678 nh]

The clue is in your picture.

That bit of red wire does nothing for being a RF ground and the way the mount is construed you've effectively not got one. If you're OK with drilling holes then a Breedlove Ball mount in the rear quarter panel under the window on the side would be a better idea. One of these puppies

https://breedlovemounts.com/CB_antenna_ballmount.html

with one of their backplates.

https://breedlovemounts.com/Backing_plates.php

Also if i go in local an turn down rf to 2 it goes away but i wanna b wide open rx.

 

[678 nh]

The clue is in your picture.

That bit of red wire does nothing for being a RF ground and the way the mount is construed you've effectively not got one. If you're OK with drilling holes then a Breedlove Ball mount in the rear quarter panel under the window on the side would be a better idea. One of these puppies

https://breedlovemounts.com/CB_antenna_ballmount.html

with one of their backplates.

https://breedlovemounts.com/Backing_plates.php

If u thi k i will get a better rf ground with ball mount? Would i still need 2 run a strap 2 frame..
Frame is welded to bodey...im goin on a ground loop now lol idk u got me thinkin now may b my mount is set up more geared towards dc ground idk man wat u think

 

[678 nh]

The clue is in your picture.

That bit of red wire does nothing for being a RF ground and the way the mount is construed you've effectively not got one. If you're OK with drilling holes then a Breedlove Ball mount in the rear quarter panel under the window on the side would be a better idea. One of these puppies

https://breedlovemounts.com/CB_antenna_ballmount.html

with one of their backplates.

https://breedlovemounts.com/Backing_plates.php

I think a ball mount puts my antt. Closer 2 my bodey thats bad my bracket sets it out but maybe a ground strap instead of wire

 

[678 nh]

The clue is in your picture.

That bit of red wire does nothing for being a RF ground and the way the mount is construed you've effectively not got one. If you're OK with drilling holes then a Breedlove Ball mount in the rear quarter panel under the window on the side would be a better idea. One of these puppies

https://breedlovemounts.com/CB_antenna_ballmount.html

with one of their backplates.

https://breedlovemounts.com/Backing_plates.php

Would i hav to sand to bare metal to match the diameter of outside plate then mayb a thin layer of silicon arround the out side so it dont rust out. Sorry for all the ?

 

[678 nh]

The clue is in your picture.

That bit of red wire does nothing for being a RF ground and the way the mount is construed you've effectively not got one. If you're OK with drilling holes then a Breedlove Ball mount in the rear quarter panel under the window on the side would be a better idea. One of these puppies

https://breedlovemounts.com/CB_antenna_ballmount.html

with one of their backplates.

https://breedlovemounts.com/Backing_plates.php

Or what if i made my bracket out of copper. At least now i understand that braided strap is better 4 rf ground. An the guys with the 3 mag mounts must b doin that 4 ground not so much 2 hold down a lil antt. Got me thinkin

 

[M0GVZ]

Swr 1 to 1.

Means nothing. SWR means absolutely nothing. A low SWR can be made up of various levels of impedance far away from what we want depending on the reactance.

the 12 gauge wire is grounded to frame an mount bracket welded to body think thats gd..

For DC. RF is not DC. It comes as no surprise that Bells CB told you to do it because they basically don't have a damned clue. As soon as someone mentions using wire then you can pretty much guarantee that their advice is worthless. I would also be hesitant to take a CB there because RF is AC, AC works on skin effect and this is fundamental 1.01 level electronics so if they don't even know that are they really competent enough to have their hands in your radio?

You will get a better ground with a ball mount mounted on the body panel or the roof and you wouldn't need a ground strap. The aim of the game is to make as much of the RF flow over the surface of the vehicle as possible, not the lossy ground below it. When using those backplates you don't sand the body down.

Have a read of the following and implement what is contained within.

Lesson 1.

Lesson 2.

At the end of the day you really need to get an analyser on the job and that'll give you an indication of how well you're doing. It'll also save you a whole bunch of wasted time. Until then just implement to the best possible the things contained in the two above links.

Some suggestions for noise here.

http://k0bg.com/rfi.html

But the footnote from that page is worth taking note of:

"Install your radio gear, antenna, wiring, bonding etc. first, following the recommendations herein. Once you're done, then (and only then) assess what extra work needs to be done. If you just throw the radio in the vehicle, and stick on the antenna like it was a piece of duck tape, you're going to get a false impression of the real level of RFI."

 

[678 nh]

Means nothing. SWR means absolutely nothing. A low SWR can be made up of various levels of impedance far away from what we want depending on the reactance.



For DC. RF is not DC. It comes as no surprise that Bells CB told you to do it because they basically don't have a damned clue. As soon as someone mentions using wire then you can pretty much guarantee that their advice is worthless. I would also be hesitant to take a CB there because RF is AC, AC works on skin effect and this is fundamental 1.01 level electronics so if they don't even know that are they really competent enough to have their hands in your radio?

You will get a better ground with a ball mount mounted on the body panel or the roof and you wouldn't need a ground strap. The aim of the game is to make as much of the RF flow over the surface of the vehicle as possible, not the lossy ground below it. When using those backplates you don't sand the body down.

Have a read of the following and implement what is contained within.

Lesson 1.

Lesson 2.

At the end of the day you really need to get an analyser on the job and that'll give you an indication of how well you're doing. It'll also save you a whole bunch of wasted time. Until then just implement to the best possible the things contained in the two above links.

Some suggestions for noise here.

http://k0bg.com/rfi.html

But the footnote from that page is worth taking note of:

"Install your radio gear, antenna, wiring, bonding etc. first, following the recommendations herein. Once you're done, then (and only then) assess what extra work needs to be done. If you just throw the radio in the vehicle, and stick on the antenna like it was a piece of duck tape, you're going to get a false impression of the real level of RFI."

Wow thanku. Yea bells said run braided strap. But now im learning thanx 2 u that rf ground is diff. An how some base stations actually tune there ground plane which is a lot harder in the mobile but if i go flat to the bodey i will get a better reflective rf ground an that in the center of roof is best but not for my 4×4 but the gd thing is i have a uni bodey that might help..i will go will ball mount on rear quarter, add a couple ferrite chokes close 2 radio an change the extra ground wires i put on case of amp an radio to strap. If this doesn't give clear wide open receive then i gotta go back under the hood i did ground my batt. To the fender with a 10gauge wire maybe replace with a strap. Tx 4 ur patients an explaining an sending links i will read up more.

 

[678 nh]

Magmount or fixed mount?

Cant find my ball mount. Would it work as well if i were to bolt my mirror bracket rite to the panel or should i spend the money an buy the one u showed. The mirror bracket would go flat rite to it, might work better but i dont wanna drill twice so i thought id run it by you .thank u

 

[M0GVZ]

Cant find my ball mount. Would it work as well if i were to bolt my mirror bracket rite to the panel or should i spend the money an buy the one u showed. The mirror bracket would go flat rite to it, might work better but i dont wanna drill twice so i thought id run it by you .thank u

Not ideal if its a door but if you insist then a mount using the bolts which fix the mirror to the door is better than one that clamps around the mirror arms and you'd need to make some braid straps to bond the door to the body. What about mounting on a front fender?

Going back to the picture you posted, if that bit of the bracket that the antenna socket went through was bolted directly to the body rather than clamped around the metal bit you have welded on then that would be quite good. An alternative is if that black bracket it clamps round could be remade so its in an upside down L shape with a hole in for the antenna mount and welded in the same position to the rear quarter that would improve things. Clamped around that metal bracket as it is isn't really the best.

Depends on how much butchering up of the car you want to do. Hole in the roof isn't only the best option for performance but is usually the tidiest way of doing it. Stick a base loaded antenna (K40/Sirio 5000 etc) on it with a long flexible whip and the whip should have enough bend in it that you don't really need to keep removing the antenna to go under low overhead objects. My Little Tarheel 2 has a 6.5ft long whip on it and I regularly go under low overhead objects such as height barriers where they're only a couple of feet higher than the bottom of the whip so it gets folded over at a right angle. Never caused an issue. Here's a picture of it. If it doesn't cause an issue on that with a Tarheel mounted with a lip mount then a K40/Sirio 5000 shouldn't cause an issue being roof mounted on yours.