Topband: Rx splinter

[John Kaufmann]

It just realized that the number of turns I specified (in my post below) to
use on the Fair-Rite binocular core will be a tight fit inside the core.
The number should be scaled down as follows:

5 turns of 28 AWG magnet wire on the source side and 7 turns center-tapped
on the load side.  That will work. 

73, John W1FV

-----Original Message-----
From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of John
Kaufmann
Sent: Saturday, February 2, 2019 11:56 AM
To: topband at contesting.com
Subject: Re: Topband: Rx splinter

The BCC splitter design suggested by PC2A is based on the "magic tee"
splitter.  An excellent tutorial on magic tee splitters can be found on
W8JI's Web site:    https://www.w8ji.com/combiner_and_splitters.htm.  These
splitters are very easy and inexpensive to build.  

A 1:2 splitter design using a single ferrite core can be found here:
http://michaelgellis.tripod.com/magict.html.  See Figure 7.  There is -3 dB
throughput from the source to each load port.  This splitter introduces a
180 degree phase shift between the two output ports but this is irrelevant
for splitting a receive antenna between two receivers.  I have built many of
these using Fair-Rite 2873000202 cores.  For a 50 ohm system, change the
37.5 ohm resistance to 25 ohms.  Use 7 turns (28 AWG magnet wire is
suggested) through the binocular core on the source side and 10 turns
center-tapped on the load side.  This will provide a 50-ohm input impedance
on all ports and excellent isolation (>25 dB) between the two load ports.

73, John W1FV