A RTTY Tutorial for beginners IW5. EDI Simone. RTTY Tutorial. This document was originally posted by K4. WW on rttyinfo. net but this domain has expired since some months at time writing. Learn and research amateur radio, science, chemistry, biology, physics, math, astronomy, electronics, and much more. PORTAL to. Ive archived a copy that I believe could be usefull for beginners. This is not intended to be an etched in stone indication of how to operate a RTTY contest, so please dont take it that way Whatever works the best for you, is what you should do, as long as it allows your participation to be fun These hints were obtained from RTTY contesters, world wide, and only reflect how they try to make their operation more efficientLearn software, creative, and business skills to achieve your personal and professional goals. Join today to get access to thousands of courses. The more efficient we make our contest exchanges, the more efficient we make it for all involved Band conditions certainly play an important part in the exchanged data, so establishing a different buffer could make your exchange more efficient in not so good band conditionsThere are many web sites to obtain RTTY contesting information, and for fear of slighting anyone, I will only suggest that if you intend to participate, regardless of the level, that you visit rttyjournal and acquaint yourself with the rules, or at least the necessary exchange Subscribing to rttycontesting. RTTY operators, especially those primarily interested in contesting, can be found here. Someone there can answer most any question that you may haveSome contest managers do not allow points for unique callsigns in the submitted logs There are varying definitions of unique, or the specific number of logs that a callsign must appear in to not be classified as unique Having this knowledge, if you choose to just work your friend just to give them a point, make sure that you work a few 4 5 others, to insure that the contest manager will allow the contact with your friend RTTY For Newcomersby Bill, W7. TIRTTY is a fun mode and easy to operate, but there are some questions every newcomer has. Please take a moment to read the following and much of the mystery will disappear. MARK AND SPACEA RTTY transmitter sends out a carrier that shifts back and forth between two frequencies. There is no amplitude modulation, only a pure carrier which shifts frequency. Bentley Staad Pro V8i 64 Bit. The lower RF frequency is known as the SPACE frequency and the upper RF frequency is known as the MARK frequency. The difference between the two is known as the SHIFT. For amateur radio, the SHIFT has been standardized at 1. Hz. It is customary to refer to the MARK frequency as your operating frequency. For example, if you say you are transmitting RTTY on 1. Hz, which means your MARK frequency is 1. Hz and your SPACE frequency is 1. Hz lower, or 1. 40. Hz. While 1. 70 Hz is the standard shift, sometimes you will find stations using a shift of 2. Hz, but dont worry about it. Your equipment will copy it fine in almost all cases. FSK and AFSKYou will often hear the terms FSK and AFSK when talking about RTTY on the HF bands. FSK means Frequency Shift Keying and AFSK means Audio Frequency Shift Keying. Regardless of which method is used, the RF signal sent out over the air is identical. MARK is always the higher RF frequency and SPACE is always the lower RF frequency. If the transmitter is operating properly, the station receiving the RTTY signal can not tell any difference at all. So what is the difference Its the way your transmitter generates the RF signal. With FSK, your transmitter receives a simple on off signal which causes the carrier frequency to shift back and forth. This signal may come from a TNC Terminal Node Controller such as a Kantronics KAM, an AEA PK 2. HAL DXP 3. 8 or some other, or it may come from a soundcard program via one of your computers com ports. FSK is simpler, easier and more foolproof than AFSK and is highly recommended if your transmitter supports FSK input. Check your owners manual if youre not sure. Since not all transmitters support FSK input, there is another method available AFSK. AFSK can be used with any SSB transmitter. AFSK is a bit trickier to set up and use, but when it is done correctly, it works just as well as FSK and will transmit a perfect RTTY signal. Also, AFSK can do some things FSK can not, such as Automatic Frequency Control AFC of the transmitter. With modern transmitters, drift is not a problem and transmit AFC is generally not needed. With older tube type equipment, it may offer some advantage. To operate with AFSK, you put your transmitter in the SSB mode instead of FSK mode, and you put an audio signal into the microphone input some transceivers have a rear connector for audio data input. When you transmit your TNC or soundcard will put out a pair of audio tones that cause your transmitter to send the required RF output. Sounds simple, right Heres the tricky part The tones are two simple sine waves, but the frequency and amplitude of the tones is critical. Lets say you want to transmit on 1. Hz, as in the previous example. Remember that your MARK signal has to be on 1. Hz and SPACE 1. 70 Hz lower. How do you do that with AFSKHeres how. With your transmitter in the LSB mode Lower Side Band, whatever frequency goes into the microphone input will be subtracted from what your dial says and be transmitted on that frequency. For example if your dial says 1. Hz and you put in a 1. Hz audio tone, your transmitter will put out an RF signal at 1. Hz, exactly 1. 00. Hz lower than your dial. So in this case, if the 1. Hz represented your MARK signal, you would have to set your transmitter to 1. MARK signal would be transmitted on 1. Ok so far Now, what about SPACE Remember, you want your SPACE signal to be transmitted 1. Hz lower, on 1. 40. Hz. What audio tone will give you 1. Simple 1. 40. 81. Hz. So the MARK audio frequency is 1. Microsoft Sql Server 2005 Compact Edition Enu Download Yahoo there. Hz and SPACE is 1. Hz. There you have the basics of AFSK. Your TNC or soundcard generates the two audio frequencies and your transmitter converts them into two RF frequencies. For technical reasons related to harmonic generation, audio frequencies of 1. Hz and 1. 17. 0 Hz are NOT recommended. They are used in this example just to keep the math simple. The recommended audio frequencies are 2. Hz for the MARK audio frequency and 2. Hz for the SPACE audio frequency. Trimble Dc File Editor'>Trimble Dc File Editor. Making the frequencies higher like this will reduce second harmonics while keeping the tones within the passband of your SSB transceiver. If youve been paying close attention, you may have noticed the SPACE audio frequency is higher than the MARK audio frequency, just the opposite of the RF frequency. This happens because youre using lower sideband. If you happen to forget and set your transmitter to USB instead, two things will happen. Because your MARK and SPACE are now reversed in your receiver, any RTTY signals you hear will not print correctly. All you will see is random characters that make no sense at all. The other thing is that YOUR transmissions will also be nonsense to the other guy. So just remember always use LSB. In the real world of course, sometimes USB gets selected accidentally. Nearly all software has a means to quickly reverse the tones, either a keyboard command or an on screen button to click. When you have a station tuned correctly but all you see is nonsense printing reverse the tones. Now you can print the other fellow and tell him he is upside down, as its called. After he reverses himself, just reverse again and you will both be back to normal. Also, you should know that in some parts of the world, especially Europe, the standard is to use USB instead of LSB.