Re: [TenTec] Tuner

[Richards <jrichards@k8jhr.com>]

OK... that provides a way sense and measure it.

What amount is too much?

But, do I really need to buy a specialize meter to determine the matter? 
  Are there no other signs or SYMPTOMS which indicate some sort of 
PROBLEM exists that may be caused by transmission line radiation?  If 
not, what adverse reactions or problems should I be having if this is a 
significant problem.
I already have a 4:1 balun and a choke on it.  What is the cure if I 
discover significant radiation from the transmission line?
PS - These are serious questions and not intended as an argument.

Thanks.

---------------------  K8JHR  -------------------

On 7/10/2013 1:28 AM, Rick - DJ0IP / NJ0IP wrote:
> James, you can tell the same way you can tell if your power supply is
> putting out any voltage: measure it.
> CMC flows on the outside of the coax, not on the inside.
> Use an RF Ammeter with a clip-on sensor.
>
> Most people build their own simple circuit for measuring CMC.
> GM3SEK (of RSGB) describes a simple circuit you can build.
> If you don't care to build, you can buy a meter starting for about 50 bucks.
>
> I purchased the MFJ-854 for about 100 bucks.  It costs more, but is
> sensitive enough to measure CMC even when using an analyzer as a signal
> source.
>
> The only thing you must be careful of is, the readings vary depending on the
> position of the coax within the sensor.
> In order to assure I always have apples to apples comparison, I built a
> short 1 ft. long RG-213 stub with PLs on each end, wrapped a bit of tape
> around it in the middle and clamped my meter over it.  It's a snug fit.
> That way I can insert the coax stub at any position I wish to measure and
> always get an apples to apples comparison.
>
> Of course if you want to see the variances of CMC along your coax (and they
> can be huge), then you have to remove the coax stub.
> For more info on how CMC varies along the coax, see Steve's (G3TXQ) page on
> RF Chokes, and read the bottom of the page.
> You find it here:  http://www.karinya.net/g3txq/chokes/
>
> 73
> Rick, DJ0IP
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Richards
> Sent: Wednesday, July 10, 2013 6:47 AM
> To: rmcgraw@blomand.net; Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] Tuner
>
> Golly fellers, I guess I feel pretty foolish now, because, until today, my
> OCF dipole was working pretty well, with no evidence of feed line radiation.
>
> How can I tell if there is unwarranted feed line radiation?  I see no
> evidence of it, and my antenna analyzer says all looks pretty good, and
> cannot imagine how I went so far wrong?
>
> ----------------  K8JHR  -----------------
>
>
>
> On 7/10/2013 12:18 AM, Robert Mcgraw wrote:
>
> > All of this as well as others posting says typically the OFC antenna
> > is problematic in nature.
>
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