You need a trifilar winding, i.e. wind it using three parallel wires.
Then connect wires in series, just as if you had three separate windings.
To match 50 Ohm to 22 Ohm proceed as following.
Let the "bottom" end be the common ground for 50 and 22 Ohms.
The the "top" end represents 50 Ohm terminal, and 22 Ohm terminal
is at "two-thirds".
Determine the optimum number of turns by connecting 22 Ohm resistor
and checking for SWR bandwidth at 50 Ohm terminal. A couple of quick
experiments will land you on the right number.
It's good to keep all 3 wires close at all times,
and also to make all terminals as short as possible,
including those forming the series connections.
73,
Sinisa YT1NT, VE3EA
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
|