PI-EL is one of the programs
included on the Bonus CD accompanying the ARRL
Current revision is 2.17; revision history is at
the bottom of this page
This program is designed to facilitate the design of PI and
PI-L networks as used in transmitter output networks.
*The demise of "tubes"
("valves") has been reported. This is erroneous.
- The design screen accepts inputs for
the operating frequency, the load as seen by the final
amplifier tube *, the
intermediate impedance (if the L-network is to be used),
the output load value and the Q value for the
- The above values have defaults for
program startup. After using the program, your current
values are saved for easy program restart.
- In addition to simply entering values
into the text boxes, "tuning" buttons allow tuning the
intermediate impedance up or down in 1% steps and
immediately seeing the new component values on the
- The Q value for the PI network is
entered and tuned in that same manner.
- Regardless of whether an "out of
bounds" value is entered via a textbox or by tuning, the
program examines the values and limits them to values
which are acceptable.
- Click on the Plot button and see
transmission and return plotted. On the plot are
indicated the responses for the fundamental, the second
and third harmonics. Those items are also shown in
tabular form at the bottom of the screen.
- After the design has progressed to a
particular point you may click on Save to save the
plot. Later you may recall that plot by clicking on the
- Design methods using tables are now
|Here are screen dumps from the program. Click on
these images to see the larger versions; use your
brower's BACK button to return.
Load Help screen:
Inductor Design screen:
Updated to 2.17 - Interface and cosmetic
upgrades; allow entry of value of generator output
impedance (seen looking back into generator) for
Updated to 2.16 - Conditional plotting error
(Rmid=Rload) found and fixed; minor interface
Updated to 2.15 - Graphics revised
Updated to 2.14 - Near-total rewrite of Design
screen to include a reduced-size plot on that same
Updated to 2.13 - Significant upgrade to
Design and Help screens
Updated to 2.12 - Minor changes to a page
label and the last-session file
Updated to 2.11 - Improved minimum-Q error
Updated to 2.10 - Added piracy notice to
program opening screen
Updated to 2.09 - Deleted generic Spice
netlist writer, added LTspice schematic writer
Note: Tonne Software has no
connection with Linear Technology
Updated to 2.08 - Corrected total-network
phase error, minor interface and printed-output
Updated to 2.07 - Simplified input-termination
entry now based only on power and peak plate
Updated to 2.06 - Correct item-placement
errors on high-resolution monitor screens
Updated to 2.05 - Add inductor-winding
routine, clarify volt and amp stress numbers.
Updated to 2.04 - Add peak voltage across each
capacitor and RMS current through every part, based
on the power entries.
Updated to 2.03 - Add significant help screen
for input termination (plate load) entry; you
may specify voltage and power (or voltage and
current) and have the progran calculate the input
Updated to 2.02 Show phase angles during
tuning, allow save/get data plot for comparison
Released as 2.01 - 1 February 2006
Copyright © 2006-2013 James L.
Tonne. All rights reserved.