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Text File | 1994-03-27 | 14.0 KB | 371 lines

cwspeed.doc Mar 12, 1994 CWSPEED - CW SPEED MEASURING PROGRAM DOCUMENTATION CWSPEED.EXE was written to establish a computerized and definitive method for calculating CW speed by two different methods. (5 letters per word, and 50 bits per word) The program was specially written for use at the Palm Beach County Hamfest High Speed International Morse Code Contest, held every October. The program is written in Power Basic (tm) which is an updated version of a fast compiler type BASIC, formerly known as Turbo Basic. The author's computer is an IBM Clone, running DOS 6.0, at 12 MHZ., using 80286 architecture without a math coprocessor. I will be happy to furnish the source code to anyone who sends me a SASE large enough to hold 6 computer output pages of text. My address is: Ted Herrman, AE8G 2827 Finch Drive Holiday, Fla. 34690 NOTES ON CALCULATIONS: 1. One may calculate CW speed by counting the number of characters in a continuous block of "copy". Letters have a weight factor of 1, numbers and punctuation have a weight factor of 2 since they tend to take longer to send. The total number of words is defined to be the above sum counted in 60 seconds, divided by 5. While this method is easy, it is imprecise. Any given piece of text may contain more or less numbers or punctuation, or an uneven distribution of words with easy or difficult letters. Nevertheless, this figure is calculated, displayed and labelled as: "Apparent Speed". 2. A second, more precise way to calculate CW speed is to count every dot and dash and every piece of time between them and between words. In this program, the methodology assumes the classical structure for CW. That is, a strict definition for how the characters are built, as follows: The length of time required to send one dot is called a bit. The length of time required to send one dash is 3.0 bits. The length of time between adjacent parts of a character is devoid of sound and has the exact length of one bit. The length of time between adjacent letters is 3.0 bits. The length of time between adjacent words (a space) is 4.0 bits. With this architecture, a word is defined to be 50.0 bits. (It so happens that the word "PARIS" followed by a 4 bit space contains exactly 50 bits. ) P .--. 11 bits + 3 = 14 cum 14 A .- 5 + 3 = 8 22 R .-. 7 + 3 = 10 32 I .. 3 + 3 = 6 38 S ... 5 + 3 = 8 46 space 0 + 4 = 4 50 Note that from the instant the end of the last dot of the "s" is sent to the instant the first dot of the following "p" is sent, 7 bits of soundless time exist. The program calculates speed on the 50 bit per word principle by counting every bit in a body of text copied by a contestant, dividing by the amount of time required to take down the copy, and then dividing by 50 and declaring this to be: " Actual Speed". The program displays both figures ( 5 char/word, and 50 bits/word) on the screen. If you use a computer to send the text, you will find that its precision is very great. Under those conditions, if you know the real rate the computer is sending versus the speed you tell it to send, you will find that the result of the calculation method above will agree with the real rate that you have measured. To measure the real rate your computer sends copy at, create or use the PARIS.ASC file also appearing on this disk. The file consists of the word PARIS, followed by a single blank space, repeated many times. Using a stop watch, count the number of times the word is sent in exactly one minute. Set a very high speed rate from your computer or keyboard to get as much precision from this experiment as possible. Estimate right down to the part of a word if you reach 60 seconds in the middle of the word. Divide the actual counted number of PARIS's by the speed you told the computer to send at, to calculate a ratio. You will find that this ratio remains constant even at other speeds. To use the program CWSPEED, a contest official keys in verbatim copy provided by a contestant. Once entered, the computer checks every character to insure that only acceptable characters were taken down by a contestant. The ARRL Rules are well known and inflexible for the conditions under which copy is to be taken down. One part of them describes exactly what characters are allowed or disallowed. The rules also spell out that a contest must provide at least 1 minute (60.0) seconds of continuous copy. Harry Lewis, W7JKJ gave me a copy of the ARRL rules. These rules must be followed to the letter in case a new world CW speed record should be attempted. In a contest, the officials announce the speed to be used to send characters. In the West Palm Beach Contest, a computer program is used to send the copy. The computer is told the speed to send at by touching the ALT + W key combination and then entering the desired number of words per minute. The program is called CW and was written by Dave Freese, W1HKJ. One can obtain it from Shareware sources. The program refers to the above ALT W speed. Based on this number, the program also calculates exactly how much time the contestant required to take down his or her copy. The computer program checks to see if the contestant actually provided a full 60 seconds of continuous copy as required by contest rules. WALK THROUGH OF SCREENS AND EXPLANATION Display: *********************************************************************** * INTERNATIONAL MORSE CODE SPEED MEASURING PROGRAM * * Written by * * Ted Herrman, AE8G * * 2827 Finch Drive * * Holiday, Florida 34690 * * Tel 813-937-5931 * * Version 2.0 Mar 9, 1994 * * * * Push CTRL + BREAK key combination for immed exit at any time. * * * * Touch any key to proceed: * *********************************************************************** Explanation: The authors ego line Display: *********************************************************************** * Enter bits per word. (PARIS = 50) is standard. <CR> = default = 50 * * Written by * * <CR> means: Touch CARRIAGE RETURN or ENTER key. * *********************************************************************** Explanation: Unless you use a military standard or some other alphabet, 50 bits is the standard number of bits in use throughout the United States. Touching the ENTER key will cause the program to use 50 as a default. Display: *********************************************************************** * Do you wish to produce calculations or exit the program? * * Enter either <CR> for calculations or 'EXIT". * *********************************************************************** Explanation: This is an opportunity to gracefully exit the program. There are other ways to exit the program, and no harm will result from the use of any of them. Display: *********************************************************************** * Enter computer CW program average speed setting - (Alt W speed.) * * This must be an integer from 5 thru 100. * *********************************************************************** Explanation: Enter the number of words per minute that the transmission was sent at. If you use program CW, then enter the number you keyed in after first touching ALT + the W key. Display: *********************************************************************** * Enter ACTUAL / REQUESTED speed ratio. Use a decimal point. * * No. of times PARIS in 60 seconds / Requested computer speed. * * For example: Actual speed 58.0 wpm * * ---- then ratio = .96667 * * Requested speed 60 * * * * You only have to enter this once per program execution. * *********************************************************************** Explanation: If you use a computer or keyboard, determine the actual number of times it sends the word PARIS, (followed by a single blank), with as much precision as you can. Divide this number by the speed you told it to send at, to make a ratio. You will find that in the case of a computer, this RATIO will hold constant later on, even if you change the requested speed. Because of the constancy of the rate, you need only enter this ratio once. Program logic will avoid subsequent requests for you to enter the number again. If for some strange reason, the ratio does not hold constant, you will have to start the program from scratch so the logic is executed fresh, and asks you for the ratio. (Programmers would probably want to modify the code in this event, and I will make it available to you, if you send a SASE.) Suppose for example, you ask your computer to send the PARIS file at a rate of 95 wpm. By actual count, you count 98 occurrences of the word PARIS and PA of the 99th word. PA contains 22 bits of the total 50 bits and is .44 of a PARIS. Then the ratio is 98.44 / 95 Enter 1.0362 at the ratio prompt. 5 significant digits are more than enough to preserve accuracy. Display: *********************************************************************** * Enter the contestant's lines of copy, including multiple spaces. * * Take as many separate lines as necessary. * * Enter as many as 80 characters per line. * * For multiple line input, change lines in the MIDDLE of a word. * * Signify end of input with 1 asterisk on a separate line. * *********************************************************************** Explanation: Re key in exactly what the contestant copied. Note that the contestant apparently made an error in the last word (antenna). See below. You must scan the input for errors and stop keying in at that point. Look for long strings of good consecutive copy. Make your input IDENTICAL in every regard to what the contestant copied with the exception that you will make your carriage returns in the middle of a contestants word. This will insure that no extra blanks appear where they should not. This would penalize the contestant unfairly. Also note in the example below that the contestant put two blank spaces after the end of the first sentence and one blank space after the end of the second. FOR EXAMPLE: The following is a picture of what a contestant wrote: "Although the extended double Zepp antenna has been in just about every antenna handbook since the year one, hams seldom use it. Its overall length is 1.28 wavelengths, and it radiates bidirectionally broadside. Fed with open wire line and a balanced antenna tuner, it also makes a fine multi band anten" HERE IS WHAT YOU KEY IN: NOTE THE LONE ASTERISK AS THE LAST LINE. Although the extended double Zepp antenna has been in just ab out every antenna handbook since the year one, hams seldom us e it. Its overall length is 1.28 wavelengths, and it radiate s bidirectionally broadside. Fed with open wire line and a bal anced antenna tuner, it also makes a fine multi band anten * The computer will ask you to verify that what you have keyed in, is an exact match for the contestants copy. Reply "YES" or "y", otherwise you will have to re-enter the contestants entire copy again. PROGRAM OUTPUT 1. The computer checks each and every character to verify that no illegal characters were sent and/or copied. Legal characters are: alphabet, digits, comma, period, question mark and fraction bar (slash). Nothing else is legal, according to ARRL Rules. If no illegal characters are found, the screen will show: "All input is legal." If illegal characters are found, the entire text is put on the screen and the illegal characters are identified. 2. The program displays the total number of bits counted, the total words counted, the total characters counted, and the amount of time the contestant needed to copy the text entered. From these statistics, one may manually verify the displayed, calculated speeds that follow on the same screen. I wish to acknowledge the assistance given to me by Harry Lewis, W7JKJ. Harry is a living legend and a goldmine of advice about CW contests and procedures and CW speed measuring algorithms. Any inaccuracies or omissions in the program are my responsibility alone. Please write with your comments and criticisms and etc. 73 and di di di dah di dah. Ted Herrman, AE8G.