[Skimmertalk] 6m

N4ZR n4zr at comcast.net
Thu Jun 15 21:49:20 EDT 2017


I believe that the input impedance varies dramatically with frequency, 
having been measured by one of us 6-9 months ago.  Nothing's ever simple...

73, Pete N4ZR
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On 6/15/2017 8:53 PM, Bob Wilson, N6TV wrote:
> On Thu, Jun 15, 2017 at 12:45 PM, a45wg <a45wg at sy-edm.com> wrote:
>
>> And why a 1:9 in front ?
>
> The Red Pitaya has a high impedance (1K ohm?) input.  They're now offering
> a 14:1 transformer (1000/14 = about 71 ohms), but it's not up on their web
> site yet.  But 9:1 transformers are more common as beverage transformers,
> and they will probably work almost as well.
>
> 73,
> Bob, N6TV
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