BC.EXE a PC program for boom corrections

(July 25 2011)

This computer program uses expressions and parameters determined from an experimental study of frequency shifts inside a metal cage.

The program takes the text file INPUT.BC as input. Note that the input is ordinary FORTRAN format so the data must be placed exactly in the correct columns on each line.

The first line is the frequency of operation in MHz. The frequency must be given with a decimal point. The remaining lines contain data for a boom plus element combination in the following format: The decimal points must not be left out.

Col 1 Boom tube cross section. 0=round 1=quadratic
Cols 2-11 Boom tube outer diameter in mm (side length if quadratic)
Cols 12-21 Boom tube wall thickness in mm.
Cols 22-31 Hole diameter in mm.
Cols 32-41 Element diameter in mm.
Cols 42-51 Element length in mm.
Cols 52-61 Distance to nearest boom tube end.
0 or blank if element not close to end of boom tube.

columns ruler
below are the first lines of INPUT.BC
0 16.0 1.5 8.0 6.0 930.0
0 20.0 1.5 8.0 6.0 930.0
0 25.0 1.5 8.0 6.0 930.0
0 30.0 1.5 8.0 6.0 930.0
0 40.0 1.5 8.0 6.0 930.0
0 50.0 1.5 8.0 6.0 930.0

Download BC.EXE (zipped, with source code, 25904 bytes) and study how the boom correction varies with the input data. Then change the INPUT.BC file to produce the boom corrections for your next yagi project.

The source code contains everything to compile with mingw32.

Download mingw516nasmplus.zip (24347473 bytes) and unpack it in the root directory C:\ to create C:\mingw32 which contains everything needed to create a new bc.exe from source code.

All the source code files of mingw, libusb-win32, libftdi-win32 and libsoft66 are available here: wincompile_nasmplus.htm