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-
- 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, π 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, Γ 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.