What I said was:
"With good quality cable, the center conductor is not radiating. However, the
shield may indeed be carrying current."
I don't think you have my meaning and have taken it out of context.
The percentage of braid coverage, the use of foils under the braid, double
braids, and aspects of the cable insulation and geometry, can be factors in
radiation. The common mode current can still be an issue, due to the direction
of the cable run and it's length with regard to frequency.
If you believe that there are no differences in various types of 50 ohm coax,
with regard to radiation from the cable, this does not agree with my
experience.
73,
Mike
W2AJI
Sent from my iPhone
> On Jun 1, 2014, at 3:59 PM, "Rick - DJ0IP / NJ0IP" <Rick@DJ0IP.de> wrote:
>
> Mike is doing it CORRECTLY.
>
> My only comment is, the quality of the coax plays NO ROLE in this.
> CMC flows on the outside of the coax shield so it makes no difference if you
> are using the best or the worst coax in the world - (as far as CMC is
> concerned; of course you should use good coax for other reasons).
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Mike
> Schatzberg
> Sent: Sunday, June 01, 2014 7:39 PM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] Trading radios
>
> In my case the RF is radiated from my Yagi and the coax shield picks up the
> radiation between the antenna feed point and the radio.
>
> With good quality cable, the center conductor is not radiating. However,
> the shield may indeed be carrying current.
>
> Stations with RFI often only experience interference with their directional
> arrays with the antenna in a certain alignment with their cable.
>
> I use a 1:1 current balun at my Yagi hairpin feed point, and the line
> isolator at the input to my amplifier, between it and the Orion II.
>
> Seems to work well with all the radios here.
>
> 73,
>
> Mike
> W2AJI
>
> Sent from my iPhone
>
>> On Jun 1, 2014, at 12:42 PM,k4elo@fastmail.fm wrote:
>>
>> Disagree Bob. Put the choke at the feedpoint of the antenna or your
>> coax will be radiating rf all the way down to the rig. If you can't
>> move the antenna, this is the most effective rfi fix.
>>
>> 73
>> Wayne
>> K4ELO
>>
>>
>>
>>> For starters, as to RFI issues, yes antenna to radio spacing,
>>> increasing same, will usually improve the issue. Be sure all equipment
> is each
>>> bonded to a common point such as the PS ground. Omit the external
>>> ground but keep 3rd pin ground intact. Use a common mode choke on the
>>> output of the radio.
>>>
>>> 73
>>> Bob K4TAX
>> _______________________________________________
>> TenTec mailing list
>> TenTec@contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
Sent from my iPhone
> On Jun 1, 2014, at 3:59 PM, "Rick - DJ0IP / NJ0IP" <Rick@DJ0IP.de> wrote:
>
> Mike is doing it CORRECTLY.
>
> My only comment is, the quality of the coax plays NO ROLE in this.
> CMC flows on the outside of the coax shield so it makes no difference if you
> are using the best or the worst coax in the world - (as far as CMC is
> concerned; of course you should use good coax for other reasons).
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Mike
> Schatzberg
> Sent: Sunday, June 01, 2014 7:39 PM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] Trading radios
>
> In my case the RF is radiated from my Yagi and the coax shield picks up the
> radiation between the antenna feed point and the radio.
>
> With good quality cable, the center conductor is not radiating. However,
> the shield may indeed be carrying current.
>
> Stations with RFI often only experience interference with their directional
> arrays with the antenna in a certain alignment with their cable.
>
> I use a 1:1 current balun at my Yagi hairpin feed point, and the line
> isolator at the input to my amplifier, between it and the Orion II.
>
> Seems to work well with all the radios here.
>
> 73,
>
> Mike
> W2AJI
>
> Sent from my iPhone
>
>> On Jun 1, 2014, at 12:42 PM, k4elo@fastmail.fm wrote:
>>
>> Disagree Bob. Put the choke at the feedpoint of the antenna or your
>> coax will be radiating rf all the way down to the rig. If you can't
>> move the antenna, this is the most effective rfi fix.
>>
>> 73
>> Wayne
>> K4ELO
>>
>>
>>
>>> For starters, as to RFI issues, yes antenna to radio spacing,
>>> increasing same, will usually improve the issue. Be sure all equipment
> is each
>>> bonded to a common point such as the PS ground. Omit the external
>>> ground but keep 3rd pin ground intact. Use a common mode choke on the
>>> output of the radio.
>>>
>>> 73
>>> Bob K4TAX
>> _______________________________________________
>> TenTec mailing list
>> TenTec@contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
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