Ordering rf choke..

[Splash1]

its time for a new coax for the imax with gpk but instead of winding a coax choke this time i want to order a premade choke..what exactly do you call them and bout how much they run ?

 

[W5LZ]

Splash1,
I'm not aware of anyone selling a 'coaxial' choke (one made by winding a length of coax into a coil). I'm sure that if you look hard enough you could find someone selling them, or who would make one for you. Considering what they are and how they are made, I'm just too cheap to buy one.
There are other kinds of 'chokes' for feed lines. Probably the second most common(?) is one made from ferrite. Several of those ferrite cylinders slipped over a section of coax and then ends put on that section of coax. There's typically quite a few of those ferrite thingys in order to be useful at whatever frequency you want it for. Naturally, since ferrite isn't 'free', it's gonna cost more than a coaxial wound choke. Again, I'm just too cheap. I ain't buying what I can easily make.
Good luck.
- 'Doc


(And no, I don't sell them things. I'm too expensive.)

 

[C2]

Doc, did you get that antenna up yet?

 

[W5LZ]

C-2,
No, not yet. If it isn't one thing, it's another it seems. My get off work time is supposed to be 5 Pm. Seems it's been closer to 8 Pm lately, for various reasons. It get's dark about 6 Pm +/- some, and with the weather like it is, forget it. I tend to speen more of that 'off' time sleeping than anything else. Ain't that the pits, wasting good beer drinking time like that? Oh well, all that over-time will pay for the solder needed to piece all them itty-bitty pieces of wire together for an antenna! It ain't easy being this cheap you know. But somebody has to do it and I'm saving you from having to be that one, right?
- 'Doc

(Now, is that an excuse, or is that an excuse!)
(Procrastination IS.)

 

[Splash1]

thanks doc..i wasnt thinkin bout a premade coax one..i thought they made a connecter type thing that would hook up to the antenna lead..anyway with that i wouldnt need bout 8 feet of extra coax..

 

[W5LZ]

Splash1,
Now you done it, you got me into the 'cheap' mode. Which is cheaper, that choke, or 8 feet of coax? (include shipping in it!)
- 'Doc


I honestly don't care how you do it (like that really makes a difference, right?) so if you want to buy one, do it.

 

[Splash1]

doc,,found on by mfj..20 some bucks , at least now i dont have to worry bout screwing up the homemade one and maybe messin up the braid of the coax..

 

[C2]

Seems that freecell is not a big fan of the coax choke anyway. The way I read his post was that they do not work very well.

 

[W5LZ]

Can't say how well they work, only that they work well enough for me. Coaxial chokes are fairly common, so they must work for other people too. They are also recommended by some commercial antenna makers for use with their products. Are they the most absolute best method of doing things? Probably not, but if it works, it works, and I'm just not obsessed with perfection. Your millage may vary.
- 'Doc

 

[niterider]

A coax choke is far better than not using any choke (or un-un) at all. Most CB antennas don't use any type of balun whatsoever, and is a culprit of much or our TVI and other forms of radio interference exist today. If you have the money, using a real choke with "toroids" or beads with the right ferrite material mix (generally 43 or 73 material), is better than just just a coax choke, it's just generally the coax choke doesn't cost you any extra money to make (as we generally have at least some excess length in our coax to make one).

 

[Moleculo]

The W2DU type balun or choke is the ferrite style you're thinking of. Here's one that's premade:

UNADILLA - W2DU In-Line Baluns

 

[niterider]

Moleculo, yes that's a good example at an affordable price. There is many makers for them though.. If one is cheap, than should at least coil the coax to create at least a coax choke.