Yeh Bry, but not on 80 and 40.
On those bands people here in Europe like to rag chew in their own language.
The requires a good NVIS signal.
The trap vertical is not much good for NVIS on 40 and not much good on 80
for DX or NVIS.
Of course we may have different opinions of the meaning of "good".
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Brian
Carling
Sent: Thursday, May 15, 2014 4:31 PM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] Eagle problem?
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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