World of Ham Radio 1997

home *** CD-ROM | disk | FTP | other *** search

/ World of Ham Radio 1997 / WOHR97_AmSoft_(1997-02-01).iso / cw / cw_11 / amsoft.iii next >

Wrap

Text File | 1997-02-01 | 35KB | 689 lines

██████ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ ██████ ███████ Version 1.04 20 September 1991 by Larry Winslow W0NFU 1520 E. Verlea Dr. Tempe, Az. Disclaimer There always has to be a disclaimer. This program has been written to the best of my abilities - I've been programming computers for 27 years now so I should be pretty good at it. The program has been extensively tested and has been found to cause no damage to files, memory resident programs, or the computer itself. I assume no liability if some condition arises which I have not tested for. A brief note This program is not free. If, after using it for a few weeks, you find the program a benefit in your shack, a $10 contribution is expected. Otherwise, you are expected to remove it and all of its support files from your system. In return for your contribution, I will provide support either via mail correspondence or phone call (as long as you pay for the long distance charges). Brief Description "CW" is a versatile program which allows a PC to receive and send Morse code for the Amateur Radio operator. Some of the more significant features of "CW" are: - Automatic tracking of received CW speed. - User adjustment of parameters defining the length of the space after a character and after a word. - User adjustment of a programmatic filter to eliminate false signals. - Code transmit speed can be either locked to the speed of the received code speed or user adjustable. - Type ahead buffer of 4096 characters allowing user to enter data to be sent in response to that being received. - Ten user defined messages which can be sent. - User definition of user call which can be sent with single key stroke. - Maintenance of 2 receive parameters allowing the tracking of multiple users. - User definition of user QTH which can be sent with a single key stroke. - Random code generator for practice. - Received data can be captured to user defined file and/or to the printer. - User defined input file which can be sent. - Help screen available with simple keystroke. - Full featured Iambic keyer with dit and dah memory. Hardware Requirements The program requires at least 128k of available memory and 1 serial communication port which will operate at 9600 baud. The program has been successfully test on XT clones, AT clones and 16mhz 386SX systems. The timing function has been designed such that it is totally independent of the characteristics of the machine that it is executing on. The only machine that it has failed to function properly was a very old, true "Big Blue" XT with only a 4.77mhz clock and that was with a very busy TSR executing; without the TSR, the program functioned properly Detailed Description My interest in a computer interface for CW was prompted by the article "ROBO-COPY" by Michael Hansen WB9DYI in the October 1990 issue of 73 magazine. The program described in the article does an excellent job of copying CW but there was no provision for sending code. Therefore, after obtaining the source file and a file describing the code receive algorithm from the 73 BBS, I rewrote the program. The original was written in C but my skills in C are limited. Therefore, I wrote my program in QuickBasic 4.5 including the transmit functionality. My receive algorithm is identical to that in the C program. The algorithm is described as "The Mean Machine". This name is not used in a slang manner but rather the method of tracking the incoming code. I quote Michael Hansen's description of the algorithm. "Before we start writing the program, we have to decide on the algorithm (method) to be used to time the dits and dahs. How does the computer decide that a "mark" (Mark is the presence of a signal, either dit or dah - space is absence of the signal) falls into the dit or dah category? A good approach to try would be to calculate the average of some number of marks. The average, or as it is call by statisticians, the arithmetic mean, is calculated by adding up a number of related values then dividing that sum by the number of values. The ARRL tells us that proper Morse timing is that a dah is three times as long as a dit. This means that the calculated mark average should be 2 dits, assuming equal numbers of dits and dahs. As you can see in the figure below, this average is an excellent point of reference for sorting marks into dits and dahs. WPM = 2.4/(average of Marks in milliseconds) therefore, 20wpm => mark of 60ms. Average DIT | DAH |________|________|________| Time in milliseconds 0ms 60ms 120ms 180ms Deviation from mean < -60ms >< +60ms > Time values for 20 wpm cw The important factor here is the number of marks used to calculate the average (mean). If that number is too small the average will become easily skewed by uneven occurrences of either dits or dahs. An example of this skew can be seen in the phrase "1000 watt"; it contains 24 dahs but only 3 dits. In this example the average would quickly converge to the length (time) of a dah. If we select a very large number (>250) of samples for the averaging calculation, we can effectively "swamp out" all but the most absurd of the "pathological" patterns that would significantly skew the average. An additional benefit to having a large number of samples in the average would be better noise immunity should an errant value enter the calculation due to QRM or QRN. A scheme based on a large sample average would work well if all cw operators could standardize on a fixed baud rate, much like the way the asynchronous serial protocols work. Unfortunately, the real world of cw is anything but standard when it comes to transmission speed. CW speed not only varies from operator to operator, but it also changes if the operator fatigues or desires to emphasize certain portions of the transmission such as signal reports, QTH, etc. There are two major disadvantages to the large sample average. The larger the number of samples used in an average, the less responsive to change it becomes. When a big change in transmission rate is encountered, such a system requires an infusion of many dozens of new mark values before it would have an accurate enough average to operate properly. During this time, much of the QSO would have been lost in a sea of garbled characters. Large sample averages are also computationally intensive, restricting their use with only the fastest machines. The MEAN Machine. ROBO-COPY's algorithm uses a smaller number of samples, 32, allowing it to "sync up" rapidly to varying transmission rates. The trick is to manage the entries that are used in the calculation of the average. First, the errant mark values due to noise are reduced by the sampling filter that qualifies each mark as it happens. Then a pre-screening function insures that skew is minimized by disallowing more than 3 successive marks of the same length, plus or minus 12.5%, from being entered into the average calculation. Another type of statistical operation used in ROBO-COPY is the mean deviation. It is used to detect large changes in the transmission speed and adjust for dah to dit rations that aren't 3:1. The mean deviation is the difference between the average and the current mark value. A record of the past 32 deviations from average is maintained. The above figure shows that under normal circumstances the mean deviation of the dit and dah are of equal value but have different signs. If you add all 32 mean deviations together the dits and dahs will cancel each other out and the sum will be near or at zero for "normal" copy. If the speed of the incoming code should change rapidly however, like when you change frequency from a 13 wpm QSO to a 50 wpm QSO, the mean deviation really "kicks in". When the value of the mean deviation exceeds 25% of the average value, the average is "opened- up" so that any mark will be included in the calculation of the new average. The program temporarily suspends the pre-screening of entries into the average in an effort to purge the average of the out-of-date values it contains. After the mean deviation recedes back below 25% of the average value the program will again start the pre-screening process using the new average as the basis for qualifications. Because of these algorithms, ROBO-COY is responsive to changing copy conditions, yet stable without being computational cumbersome." As each mark is completed, the program then starts measuring the length of the space following it. If the length of the space is less than or equal to the value of letter space value, then the space is considered to be part of the current character and the program starts measuring the length of the next mark. If not, then the character is considered to be complete and is output to the "receive" window of the screen. The timing of the space continues and if it reaches the value of word space, a word is considered complete and a space is output to the receive window of the screen. The program then waits for the beginning of the next mark. The default values of the letter space is initially 2.5 times the dit length. The default value of the word space is initially 6.7 times a dit length. Both of these two values can be changed with function keys. The Interface The program uses either COM1 or COM2 to interface to the radio equipment and to provide timing of the CW received or sent. Because a comm-port is used, the signals must conform to the RS-232 definition which is normally a -12v to +12v swing. Naturally, the radio equipment does not normally provide the proper signals and therefore some type of interface must be developed. The interface to the "key" input of the rig is simple. Wire a diode from the DTR pin of the comm-port connector to a very small reed relay (a good one would be one of the 16 pin DIP types) and then back to the GND pin of the connector. The polarity of the diode would be with the cathode connected to the connector. |\ | |----------| DTR o-----| \|-----| relay |--------+ | / | |----------| | | GND o-----------------------------------+ The contacts of the relay can then be used to key the rig. However, the interface for the receive side is not quite so simple. The October 1990 issue of 73 magazine, which contains the original article describing ROBO-COPY, includes a somewhat simple interface which does function although it is not very effective. Back in the early 70s, I received the diagram of an interface circuit which is impressive in its performance. It is so effective in digging into the incoming signal and extracting the cw present that I added a small audio amplifier so that I could use it just as a simple audio filter. It has recovered a cw signal from the receiver even when it could not be heard with headphones on. Unfortunately, I misplaced the diagram when I moved from Minneapolis to Phoenix in 1980 - if you've ever moved, you will understand how easy this is to happen. I will have to reverse engineer the device before it can be provided to the users of CW. Please forward a SASE envelope to me and I will furnish you with the schematic as soon as possible. There are two different types of connectors which can be used on a PC - DB-9 and DB-25. The following table list only the pins which are of interest to the user. DB-9 pin DB-25 pin usage Ring Indicator 9 22 input from receiver Data Term Rdy 4 20 "key" signal to rig GND 5 7 ground Clear to Send 8 5 Dit paddle Carrier Detect 1 8 Dah paddle Electronic keyer The user can also wire his keyer paddle such that the program will act as full-featured electronic keyer. This includes iambic action plus dit and dash memories. For this feature to be active, the user must include a line in the parameter file of "KEYER=YES". I have found that a simple 1488 EIA interface chip (used for some of the other required signals) with the paddle connections to the inputs of the chip provided a very satisfactory method of interfacing the keyer paddle to the program. Parameter file When the program is started, it reads in a file (which defaults to the file CW.MSG) which contains parameters defining the user and also up to 10 "canned" messages. Each record of the file begins with a keyword followed by the data associated with that keyword. Keyword Associated data MSGn= Where "n" can be 0 thru 9 defining 10 "canned" messages. The content of those messages can be any valid cw characters. One feature that can be taken advantage of is the inclusion of # followed by a "C", "Q", "N" or "I" - the pair will be replaced with the users Call, the users Qth, a program maintained Number, or Increment that number. GMT= Value necessary to adjust local time to GMT/UCT. Negative values are represented by a leading -. PORT= Hex value of the comm-port to be used. If this parameter is not present, the program will default to comm-port 1. Comm-port is "2F8". CALL= User call sign. QTH= User Qth. TONE= Frequency of the monitor. If this parameter is not present, the program defaults to 800hz. SPEED= The transmit speed to be used initially. If this parameter is not present, the program defaults to 20 wpm. KEYER= This must be "YES" for the electronic keyer feature to be available. Program start-up The program is launched with the command: CW [filename] This will start the program executing and if "filename" is included, that file will be read in place of the default file of "CW.MSG" (see description of the contents of this file above). First, the program will announce itself, wait three seconds [this can be shortened by pressing the <space> key], and then the normal screen is brought up. The normal screen consists of 4 areas: (1) the status line, (2) the receive area, (3) the keyboard area, and (4) the sending area. The information contained on the status line consists of: a) The state of the program - either RCVE or XMIT b) The current value of the receiving speed. c) The current value of the transmitting speed - this can have a value of "LK" which indicates that the transmitting speed locked to the receiving speed (see Alt-L later). d) The count of the number of characters currently in the keyboard buffer (to a maximum of 2048 characters). e) The state of the digital filter. f) The "letter" space to dit ratio. g) The "word" space to dit ratio. h) The monitor frequency. i) The local and GMT/UCT time. This is followed by the window for the data received by the program - while receiving, if the program detects a character which is invalid, it will be replaced with a @. The name of the receive window will flash when there is either printer or file capturing of received data. Also, the upper right corner of the shows which of the two sets of receive (see alt-U in special keys) is currently active. Next comes the window where the keyboard data is display that the user has entered for transmitting. And the final area is to show the user what is being sent. Just a brief warning. Do not have a "background" program such as print or a TSR running which can actively steal CPU cycles from the program. This will severely alter the timing mechanisms of the program. Operating Tips When the program is interpreting the incoming signal, it makes every attempt to properly decode the signal. However, because there is an infinite number of different "fists", it becomes almost impossible to adjust for each different operator. Frequently the user of the program must provide assistance so that the program can function as the user desires. This assistance if provide thru the F1, F2, F3 and F4 function keys. F1 and F2 should be used when the characters are translated into Ts and Es - for example, "C" becomes "TETE" - or when characters are combined - such as "AM" becomes "J". These two keys adjust the length of the space between elements of a character. Too long and the "AM" becomes "J" and too short results in the "TETE". As you use F1 and F2, the effect is reflected by the "Ltr=" value on the status line of the screen. The value reflects the "dit" time that represents the inter-letter space. The second assistance is thru the F3 and F4 keys. These keys are used to help the program determine the end of letters in a word. If the word "help" is shown as "h e l p" then the F3 key should be used. And if "help me" is show as "helpme" then F4 should be used. As with F1 and F2, when you use F3 and F4, the effect is reflected by the "Word=" value on the status line of the screen. The value represents the "dit" time that reflects the between-word space. During the development of the program, it quickly became apparent that without these function keys, the program would never be able to cope with the variety of "fists". Use them properly and the program is fully capable of showing even poor code on the screen. It is not unusual for the Rx speed on the status line to change a bit either up or down when the program is copying code solidly. This is caused by the program recalculating the receive code speed at the end of each dit or dah. The program should continue to copy the incoming code with no problem. On the other hand, if the speed should change by large values, this is an indication that the input signal is not properly tuned in such that the interface provides a solid signal to the computer -- another cause can be static crashes. "Special Keys" The program will respond to some keys other than as data to be sent. A brief explanation of these special keys can be obtained by entering Alt-H while the program is executing. The following is a more detailed description of each key. ESC This key will toggle the program between receive and transmit modes. The left end of the status line will show the current mode. Additionally if in transmit mode, the name of the Sending window will blink. F1 Adjust length of letter spacing down by .1 times of the current dit length. This key should be pressed when the received code is shown as is not separated into individual characters properly. For example, "is" is interpreted as "5". F2 Adjust length of letter spacing up by .1 times of the current dit length. This key should be pressed when the received code is shown as a string of Es and Ts. For example, "B" would be shown as "TEEE". F3 When the spaces between words are missing, press this key. This adjusts the length of the "space" between words down by .1 times the current dit length. F4 When every letter is separated by a space, use this key. Each press of the key, adjust the length of the "space" between words up by .1 times the current dit length. F5 Decreases the send speed by 1 wpm. alt-F5 Decreases the send speed by 5 wpm. F6 Increases the send speed by 1 wpm. alt-F6 Increases the send speed by 5 wpm. F7 Clear the receive window of the screen F8 Clear the keyboard window of the screen. Note that this will also change the "Buff" entry of the status line to zero. F9 Toggle the digital filter. There are 4 settings of the filter. "Low" which limit the maximum received code speed to 75 wpm but the program will be sensitive to "noise". "Med" will limit the maximum speed to 37 wpm but makes the program less sensitive to noise. "Hi" limits the speed to 18 wpm but makes the program even more insensitive to noise. And finally, "Off" which removes limits from the maximum speed but also makes the program very sensitive to noise. F10 This will reset all program receive timing parameters to their default values. alt-B This will toggle the monitor on and off. The current state can be seen on the status line. alt-H A brief description of each special key will be shown. The display can be terminated prematurely by pressing the "ESC" key. alt-I The user will prompted of the name of a file to be read and treated as if the data were keyboard input for transmission. The file will be read until end- of-file is reached or until the user presses alt-I a second time. When the file is closed, the user will be notified with a brief message on the screen. alt-L This key will lock (or unlock) the transmit code speed to the value of the receiving code speed. A brief message is shown the screen. Also, the TxSpeed of the status line will reflect the current value. alt-M This will display the value of the Call, Qth, and the 10 canned messages. alt-N Allows the user to initialize the value of "number" alt-O This provides the user with the writing of the received CW to a file. The user will be prompted for the file name. The program always opens the file in "append" mode. The file will remain open until alt-O is pressed a second time or until the program terminates. Note that any special cw characters such as "BT" will be shown in brackets - for example, [BT] - also, once a minute the date and time will be written to the file again surrounded with brackets. alt-P This function is identical to the alt-O described above except that the output is to the user printer. alt-Q Terminate program. alt-R This will cause the program to generate 63 groups of 5 characters of random code. It can be used for code practice. alt-S If the user is curious, this key will show the current state of the mean-deviation and mark tables. It is present for program debugging. alt-T Allows the user to adjust the frequency of the monitor. alt-U The program has the ability to maintain its receive algorithm values for 2 different signals. This key will flip the program from one signal to the other. This can be useful when you are in a QSO with two people are not sending identical code. Without this functionality, there would be the possibility of a brief period time when the program would receive "garbage" while it synched up with the other signal. alt-0 Send message 0. alt-1 Send message 1. . . . alt-9 Send message 9. Insert Send cw character AS Home Send cw character KN PgUp Send cw character AR PgDn Send cw character SK End Send cw character SN Delete Send cw character BK and switch program to receive mode. <enter> Send cw character BT UpArrow Send call DnArrow Send Qth RtArrow Send "number" LtArrow Increment "number" by 1. ! Send cw character AA # Send cw character KA $ Send cw character IQ % Send cw character AK Any character which is not in the above list nor represents a valid CW character will result in a Beep. And there is more! I have an ICOM IC-765 and have developed a computer interface to it. I then combined this interface with the CW program. This allows me to first tune the rig with my computer and then with the simple pressing of the F12 key, I'm in the CW program. Another press of F12 returns me back to the interface program. If you are interested in this software and have an ICOM CT-17 CI-V interface (I can provide you with the diagram of a $12 replacement for the $97.50 that ICOM wants for the CT-17), send me a 5.25 floppy along with a shareware fee of $20. This interface has proven very effective in controlling my IC-765 and recognizing when I manually assume control of it. Based upon the documentation provided to me by ICOM, the program should be equally effective in controlling other ICOM HF rigs. Change history Rev: 1.01 -- 25 July 1991 Initial release Rev: 1.02 -- 31 August 1991 Implemented calibration function. Changed initial value calculations using results of calibration function. Blanks and special characters weren't showing adjusted buffer count. Initial filter value was getting changed down to "low". Changed Welcome screen to reflect new rev number. Corrected Alt-I function - it was not working. Corrected TellClose - in case current line not at announcement. Changed OpenWindow to center message TxLock wasn t functioning Rev: 1.03 -- 15 September 1991 The help function (Alt-H) was inadvertantly changed such that it wouldn't function at all. Rev: 1.04 -- 20 September 1991 Corrected Farnsworth spacing - it was too short. Show Farnsworth speed on send area border when active. Future changes I'm currently working on a mouse interface for as many keyboard type functions as possible. Any and all suggestions are solicitied. In fact, many of the current features were the result of suggestions from hams here in the Phoenix area. If you have an idea, let me know.