ugly balun deja vu

[wavrider]

Keep in mind CMC is not the only cause of TVI/RFI so just having a yagi with a gamma for impedance match does not mean there will not be any interference to the neighbors, or your electronics.

Proper grounding methods and of course a clean signal figures into the equation,

 

[bob85]

booty aint half as daft as some folk think he is

silly me . i thought CMC's were typically (but not always) caused by lack of ground plane ..... not by lack of perfect antenna tuning .
since a tapped coil or loop can typically tune CB antennas to 50 ohms , how can a gamma tuned antenna not have CMC's but the others can ? how does the gamma stop CMC's ?

 

[wavrider]

Common mode current


In depth, technical, and detailed description of CMC.

 

[HomerBB]

Common mode current


In depth, technical, and detailed description of CMC.

Do you have a just-know-enough-to-get-by version? :blink:

 

[wavrider]

Do you have a just-know-enough-to-get-by version? :blink:

Classic.

The RF choke AKA ugly baluns work.

I use them on all the verticals I have ham bands included.

Product Pictures 2

Item 8231. 8232

The WireMan - Baluns - Assembled, Kits, Custom Designs

You can make your own just order up the ferrite core beads and make your own jumper, heat shrink it and use it.

Friend of mine lives in a crowded sub division in Ocala Fl. He uses a ground mounted vertical.

It is just aluminum tubing around 36 feet, not resonant any where. He has around 20 of those ferrite core beads at the feed point of his vertical, runs full legal limit and no tvi rfi or complaints from the neighbors. they work well. Coax feed line so just imagine the impedance mis match.

 

[Captain Kilowatt]

They are definitely NOT the be-all and end-all when it comes to RFI but they can help.Far too many electronics today have poor shielding or RF bypassing and a high percentage of RFI is caused by fundamental overload and no amount of filtering, baluns, or grounding or any such technique is going to solve that issue. I do not bother to implement such techniques simply as a matter of course because it may help but rather as needed and only if needed. So far so good in the RFI department.

 

[wavrider]

I agree CK on not an answer all to everything.

For those who have some acreage RFI/TVI is not much of an issue as no neighbors live up our backside.

In city lots and small urban yards the neighbors can hear you fart with the windows closed. Imagine what they can hear in the cheap ass Chinese made electronics being purchased at Wally World?

Any and all measures will help prevent TVI/RFI.

They are definitely NOT the be-all and end-all when it comes to RFI but they can help.Far too many electronics today have poor shielding or RF bypassing and a high percentage of RFI is caused by fundamental overload and no amount of filtering, baluns, or grounding or any such technique is going to solve that issue. I do not bother to implement such techniques simply as a matter of course because it may help but rather as needed and only if needed. So far so good in the RFI department.

 

[Wire Dawg]

I live one mile away from a commercial radio station. I was made aware that the station had everything to do (some years ago) in the shut down of one neighbor's radio. I've implemented every viable way to avoid interference. The ugly balun, a Bencher YA-1 LP filter, good grounding, conservative use of amp power, a good radio and setting a horizontal beam perpendicular to their antenna tower (major nulls towards them) are my primary tools to avoid conflict. I've really learned a lot from your exchanges, for which I'm very grateful.

 

[Mudfoot]

More than likely, the interference was suffered by a listener not being able to hear the station. Maybe they intervened on the listeners behalf.

 

[RADIOOMAN]

More than likely, the interference was suffered by a listener not being able to hear the station. Maybe they intervened on the listeners behalf.

I agree; seems like a more reasonable assumption.