Don't ICE make a receiver overload unbuilt into a lightning detection device?
Trent Sampson
0408 497550
On 31/12/2010, at 10:31 AM, "S56A" <s56a@bit.si> wrote:
> N4ZR wrote: From what W3LPL has told me, I am pretty confident that I can
> simply parallel the output of the 6 filters, but can I also parallel the
> inputs?
>
> I very much doubt that W3LPL told you that! His BPF are triple tuned
> circuits with top capacitor coupling. They exhibit low impedance on the
> frequencies above bandpass. 10 m filter is coupled to 50 Ohms with 33 pF
> while 160 m has 719 pF. That gives 475 (square) power ratio or -27 dB
> loss.
>
> Only serial tuned circuits can be paralleled at 50 Ohms and even that
> becomes difficult beyond triplexer. Check http://www.nuhertz.tv/
>
> You don't need any BPF for QS1R, just band STOP filters to prevent input
> frying from nearby TX. ICE filters might be easily converted to band-stop
> with change of both inputs to serial notch and adding just one more small
> coil for parallel resonance (de)coupling.
>
> HNY & 73 de Mario, M/S56A from London
>
>
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