I need to say that my comment was just an example.
Perhaps it is not the best example, but it was the first I found.
That model or maker is NOT my recommendation.
Apologizes for the confusion.
73, Maximo
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Richard
(Rick) Karlquist
Sent: sábado, 4 de abril de 2020 6:02
To: jim@audiosystemsgroup.com; towertalk@contesting.com
Subject: Re: [TowerTalk] TH7-DX balun info -- thanks!
Jim is exactly right. If you look at the web page
that was cited, the vendor admits that the measurement
was done with an AIM4170c "Network Analyzer." Actually,
this instrument is not a VNA, but is merely an impedance
analyzer, and is identified as such by its maker.
(FWIW, I happen to own an AIM4170)
It is impossible to make a reliable measurement of a
balun using only a single port impedance analyzer.
Wrong tool. Any claims to the contrary should be
summarily disregarded. Another problem is that only
the magnitude of the impedance is plotted. The
phase is only given at 14.195, where it is 2 degrees.
How convenient. The balun needs to be roughly
resistive across the operating band, as Jim's tutorial
explains. Not just at one frequency.
Rick N6RK
On 4/3/2020 10:21 AM, Jim Brown wrote:
> Do not trust these plots or claimed performance from this company. A
> local ham who is building a contest station gave me one of their units
> to measure. It didn't look anything like their plot. These products
> might not burn up, but I wouldn't trust them to effectively choke
> feedline current and the resulting noise pickup.
>
> 73, Jim K9YC
>
> On 4/3/2020 2:36 AM, Máximo EA1DDO_HK1H wrote:
>> For
>> example;https://www.balundesigns.com/model-1115d-max-choking-1-1-balun-1-5-54-mhz-5kw/
>>
>>
>>
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