RF - A Program to Solve a Number of Radio Frequency (RF) Related Problems.

This DOS based public domain program was written to solve a number of problems
encountered in by professional work and for amatuer radio use. The program has
a number of routines, that solves problems as diverse as designing attenuators,
finding the free space path loss, noise and IP3 of a number of cascaded stages,
selecting blower requirements for valves, designing inductors, finding the
characteristics of transmission lines (both waveguide and coaxial of various
forms), designing RF pre-amps etc etc etc. All the routines were designed to
solve a problem that I (or in some cases someone else) had, at particular instant
in time. Hence the amount of work put into the individual routines depended on
the amount time I had available, the importance I attached to the individual
problem etc etc. Many of the routines are unfinished, having served their
purpose. Some have never really been started. Others work well. 

At the present moment in time, I have not the free time nor inclination to
produce any decent documentation. There is however some built in instructions
describing the use of each routine. I would not have bothered to release the
program, but as a few people have expressed interest in the individual routines,
I have done so. Here is a list of the sort of things the program does.

0:    EXIT                             20: Path loss calculator.
1:    General Introduction.            21: Stability from Puff files.
2:    Convert real impedances.         22: 2-way microstrip power splitter.
3:    Convert complex impedances.      23: Power tube blower requirements.
4:    S parameters to lumped circuit.  24: Blower selection.
5:    S(dB) to lumped circuit.         25: Air-flow extrapolation.
6:    Series LRC circuit to S.         26: Blower performance.
7:    Parallel LRC circuit to S.       27: Flow/Pressure/Velocity conversions.
8:    Build a T, ã  or L attenuator.   28: Terminated transmission line
9:    Common source FET amp.           29: 3CX5000A7 exact flow & back-pressure
10:   Design a power splitter.         30: Induction motor speeds
11:   Filter design menu.              31:
12:   Inductor design menu.            32:
13:   Resonance and Q calculations     33:
14:   Mixer product calculations.      34: Mixer sprogs - use Minicircuit data.
15:   Cascaded NF and IP3.             35:
16:   Power conversions.               36:
17:   Series/parallel resistor.        37:
18:   Transmission line calculator.    38:
19:   VSWR, â and % reflected power.   39:

Numbers 14, 21, 22 and 34 are not really working well. I would deleted them, but
its more hassle to do that than tell you they don't work. I gave up with #11
(filter design), since there are good filter design programs around. However, it
does implement the constant impedance band-pass filter correctly, which is useful
(ie after a mixer) and not well covered in the mormal filter design programs. No
23 (blower design for valves) is not working properly, so don't use that. I do
intend sorting this out (unlike numbers 11, 14, 21, 22 and 34), but so far have
not had enough time to find the theory necessary to solve it properly. Most of
the others work - more or less. Number 9 is quite clever, as it attempts to deign
an RF pre-amp from the S-parameters of the FET used and the DC conditions form
the FET. However, it does not test all posibilities for designs, but I think any
results it gives are correct.

The program needs ANSI.SYS installed (by puting 'device =c:\dos\ansi.sys' or
similar in config.sys). The program is supplied as a compressed ZIP file, RF.ZIP.
Please ftp from medphys.ucl.ac.uk. Get the file davek\rf\rf.zip.

There are a number of text files, with the extension .txt that the program uses.
These contain help information and menues. I originally put this in the
executable, but the resulting program started to get too big to fit in a PC's
memory. By default the program rf.exe looks in the directory c:\rf for these text
files. So if you put the .txt files in c:\rf, you can place the executable rf.exe
anywhere you want, such as in your utils or bin directory - whatever you have.
If however, you wish to put the .txt files anywhere other than in c:\rf, you must
set an enviroment variable to indicate where they are. For example, if you wish
to put them in d:\rf_prog, put the following line in autoexec.bat.

set RF_TEXT=D:\RF_PROG

Hope it's of some use.

Dave Kirkby, G8WRB.

PS If you spot any bugs in the program, or understand how to do what #23 tries
to do, please let me know.