[Amps] Broadband transformers, and ferrite plate chokes

[Peter Voelpel]

Those mentioned R&S transmitting  chokes (90µH) use 25 windings on a 2 1/4"
ceramic former containing a 1.5" diameter ferrit rod 3.5" long. The wire is
#18 spacewound at 5 tpi.
Original use in 1-30MHz amps running at 3KV anode voltage, 1.3A at full
output.
Two chokes are used at right angles and one is switched out above 10MHz.
The remaining one is tapped then at 60µH as well.

I am going to use the same pair of chokes for a 2x8877 project I am busy
with.

73
Peter 

-----Original Message-----
From: amps-bounces at contesting.com [mailto:amps-bounces at contesting.com] On
Behalf Of Manfred Mornhinweg

In order to keep a ferrite core of 2cm diameter working at low enough
losses, about 100 turns of wire would be needed for a typical amp running at
2.5kV RMS RF voltage.