There are two types of decoding:
A1A - manual decoding using the human brain and ear
A1B - machine decoding by technical systems.
The distinction refers to the decoding only, encoding is not relevant. An op using a keyboard for CW generation is still an A1A op.
Let us suppose that you have never studied the Morse code yourself and that you are trying to use the PC to perform a CW QSO. The first insight is that you belong to a small minority, by far most CW op are using A1A, i.e. they decode their transmission by ear. Likewise, they generate their code using elbugs, straight keyers or bugs, i.e. their CW is less perfect than computer CW.
You will find out that some station can hardly be decoded by you machine, while others decode perfectly well. The reason is the encoding. Those who are using mechanical keys have a better chance to create corrupted text on your screen than those who are using a keyboard or a fully electronic keyer with auto-spacing. However, what looks corrupted on a screen might still be an armchair copy for a trained Morse code enthusiast.
While a screen with a chaotic text may disturb you most A1A op simply ignore/overhear little errors and other problems with inconsistent pauses as long as these problems stay within a normal margin of error. Here are a few hints that will help you to get the most out of your CW program:
• It is better to answer CQ calls over calling CQ yourself because this gives you a first idea whether or not you will be able to copy your QSO partner well enough. Start with loud signals which look nice on the screen.
• Do not mute you audio. This will help you to understand if there is interference on the frequency, moreover, it is good practice to listen to Morse code in order to train your ability to estimate the speed. Be careful with the speed setting of your Morse encoding program. Never set your encoder speed higher than the speed given by the decoder. Do not use the default value of the encoder, it may be too fast. While most experienced A1A hams can read up to 30 wpm, the average speed in QSO practice is under 20 wpm. Many CW hams with moderate activity can hardly copy 15 wpm. The conversion formula for speed units is: char/min = 5 times words/min. Example: 20 words per minute are equal to 100 chars per min. Speed is indeed your worst error source, expect CW to be much slower than most other digital modes. It is ok to start using 15 wpm if you are not yet acquainted with A1B.
• Start your first contacts outside the overcrowded DX section of the bands at the lower band end.
• Before you go on air read the manual of your digital program. Most CW programs can generate all prosigns (special symbols used in CW) but it is hard to guess the key mappings for these Morse symbols. Do not try to "approximate" a break point prosign -...- by 'bt' which will certainly generate -... - which is unpleasant in a CW qso. Do not take it for granted that the break point prosign is mapped to the key '=' (though such mapping makes sense). Consult your manual.
• Consider writing dedicated macros for CW operation, and if you do, please avoid verbosity. Remember CW is slower than PSK or RTTY. Keep in mind that most CW QSOs are slow enough that you can type directly into the keyboard. By all means avoid punctuation characters as much as you can, many CW op hate punctuation. If your language is other than English be careful with accented letters or umlauts. Your digital program might encode them incorrectly or your QSO partner might not be familiar with special Morse characters. Do NOT use your PSK macros, their style is too different from normal CW style QSOs, some PSK macros produce nasty CW code (e.g. those with dot series like Name:...........John).
• If you fill out a QSL card, just use CW. If you are brave and honest, you may use CW/A1B. Do not use A1B alone because machine decoded CW is not the only A1B available in ham radio. Feld-Hell mode is A1B, too. Anyway, there is no need to conceal that you are using a computer for decoding. On the contrary, your QSO partner might appreciate this indication and he may switch over to a CW generator which makes life easier for both of you.
• Be aware of the fact that A1B is a poor tool for DXing just like most digital modes. If you need to boost your DXCC record the best advice is to learn at least the sound of your own call sign. To monitor a DX-frequency by a decoder is bound to fail because of the qrm. Accept it as a fact that human ear and brain are hard to beat in DX pile ups.
Last but not least - be aware of the fact that A1B/CW is a relatively weak digital mode. Its main advantage is that it is an interface between operators with computers and without computers. CW is more suited to human operators. Computers are doing a better job with other codes. Do not expect miracles from A1B.
To get full access to the world of Morse code it is necessary to learn it. A1B may be a good point to have your first encounter with CW, however, A1B practice is not really helpful to learn the code. Very few A1B operators will ever be able to upgrade smoothly to A1A without a dedicated training program. Should you ever feel like learning the code it is best to take a break from A1B practice and dedicate the time to CW lessons.
The first step is to recognize an A1B op as such. A1B op are using keyboards and the generated CW tends to be impeccable. A keyboard will never send a dot too much but the op may hit a wrong key. Some A1B op send pretty fast, others may be recognized by their macros. A typical style element is the use of the loc on HF or the short 'btu' (both are rarely used by traditional CW op). What should an A1A op do when in contact with A1B?
• Do not adapt to the speed of the A1B op but use the speed that you are most comfortable with. Consider that decoders are very unforgiving, every little error or imprecision will make you look ugly on that other screen.
• If you have connected several keyers to your tx, use the one which produces the best code, first choice is a keyboard, second choice is an elbug with auto-spacing switched on. A computer will not be able to appreciate the beauty of bug swing.
• Many A1B op are newcomers, please offer them a QSL card.
The most important rule is to make your QSO partner feel happy about the QSO, there is nothing wrong with A1B, nowadays it is a typical mode to get in touch with CW. The A1B op of today may be the A1A of tomorrow. Would the old timers have learned CW had it not been compulsory? Certainly not all of them.