PI-NETWORK MATCHING DESIGN

The CE program can be used for a lot of other fun things also.
Let's say you wanted to design a PI-network match for your
old 807 running 500 volts at 100ma (assuming about 3.8 mhz)
This is Rdc=E/I=500/0.1= 5000 ohms.
This makes the RF impedance (~=Rdc/2) required at the plate 5k/2=2.5k

So we need to match 2.5K to 50 ohms with the Pi-net.

A typical Pi-net works by matching the 2.5k down to about 25 ohms
and then 25 ohms back up to 50 ohms.

Think:
25 to 50 ohms and 25 to 2500 ohms using two EL-matches back-to-back.

1) Start the program. (The default freq is 3.8 mhz) 
2) The matching network at start up is:
			 25 to 50 ohms Lm1=1.05uh   Cm1=836pf
3) Change the RL from 50 to 2500 
4) The matching network is now:
			 25 to 2500    Lm2=10.43uh  Cm2=166.5pf
5) Simply cascade the two (mirrored) for:
    Plate-to-ground   Cm2 =166.5 pf (minus about 20pf plate-to-ground cap)
    Series-L          Ls  =Lm1+Lm2=1.05+10.43=11.48 uh 
    Output-to-ground  Cm1 =836 pf

6) What fun, huh, no Class-E stuff at all.
Does this sound like the output network in your Johnson Adventurer or what?
Works for antenna matching too. Futz around with it a bit.

Regards,
BobbyT NU2B 14 May 2004