Some of them would be surprised how well they could do with the trap vertical!
Best regards - Bry Carling
> On May 15, 2014, at 2:04 AM, "Rick - DJ0IP / NJ0IP" <Rick@DJ0IP.de> wrote:
>
> Yes Jim, but that is when running high power.
> Most of the time people running antennas like these here in Europe are
> running only 100w.
> And in Carter's case, he was having problems even at much lower levels
> (though it may not be cmc on the feedline).
>
> The best solution I've found for the case you pointed out is to not use
> ferrite in the choke.
> You don't have as much impedance to cmc without the ferrite but it doesn't
> fry when running less than one KW.
> I've been doing it for 15 years.
> Prior to switching to that, I did fry a lot of baluns with much higher power
> ratings.
>
> Your suggestion for a good balun at the feedpoint works for coax fed
> antennas.
> Due to very limited space, hundreds of people here in Europe have just one
> short dipole, fed with openwire.
> They want to cover as many bands as possible, and "openwire-fed" is
> considered to be the best way to do that.
> Since link-coupled symmetrical tuners are very rare, people end up using a
> choke/balun between the openwire and the asymmetrical tuner. In fact the
> trend is to use an auto-tuner.
>
> What is your suggestion there?
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Jim Brown
> Sent: Thursday, May 15, 2014 7:47 AM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] Eagle problem?
>
>> On 5/14/2014 10:33 PM, Rick - DJ0IP / NJ0IP wrote:
>> Jim, can you elaborate on that please.
>>
>> By "not practical", do you mean from an electrical standpoint (ie. it
>> does not help) or do you mean from a physical standpoint (the
>> mechanics of building it)?
>>
>> It is done often here in Europe.
>
> N6BV has shown quite convincingly, and I confirmed his analysis, that there
> are many conditions that, depend upon feedline length and severe mismatch
> where even the most robust conceivable choke will fry with high power.
>
> The problem occurs when the SWR is quite high --for example, an 80M resonant
> dipole loaded on 40M.
>
> 73, Jim K9YC
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