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LF: Fw: Low pass filter 1 kW 136k 472 k what components to choose? Tnx t

To: Langwellen-Reflektor <[email protected]>
Subject: LF: Fw: Low pass filter 1 kW 136k 472 k what components to choose? Tnx to all
From: "Hans-Albrecht Haffa" <[email protected]>
Date: Sun, 21 Dec 2014 21:31:23 +0100
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Dear OMs,
thank You for the quick answer just in one day. Isn t it nice to get replies from technical experts just in a few hours?
I compared Your drafts with an already built construction of me using abt 80 mm ferrit toroids with cut slots and stacked mica caps 150 nF ( I nedded 30 nF, so I stacked 5 of them...). The air gaps I had cut with an saw designed to cut tiles from the home store. I measured transfer function s21 with the Vector-Antenna analyser from "Funkamateur", as it should be for an 7pole-filter.  Just before I had done trash measurements with defective BNC-cables, so I wrote an e-mail to the reflector.
 
 
Gesendet: Sonntag, 21. Dezember 2014 um 16:38 Uhr
Von: "Hans-Albrecht Haffa" <[email protected]>
An: Langwellen-Reflektor <[email protected]>, "Hans-Albrecht Haffa" <[email protected]>
Betreff: Low pass filter 1 kW 136k 472 k what components to choose?
Dear OMs,
just a question strait forward: What componnets I should choose for a low pass filter for 136 kHz and 472 kHz, two filters to be designed.
136 kHz:  Pin abt 1,5 kW
472 kHz:  Pin abt 0,5 kW
SWR: s = 1...2,5 when mated, in case of failure more
a five-pole low pass will probably be sufficient.
My Question:
What iron powder cores or air coiles will do it, known or proofed by experiment? Diameter, marterial grade?
What capacitors? max. Voltage.  High voltage caps from Wima (Ucd=4kV or 8 kV) are not available at distributors, mica capacitors will hardly fit in capacitiy value or in voltage, when in my collection.
The calculus of magnetic circuits is not a problem for me, but it is easier to start with components that will fulfill the demands.
Waiting to Your kind anwer,
55, Hans-Albrecht
DK 8 ND
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