HamRadio Tech

DIGITAL MODES: the new generation of HF HAM Radio !


Getting Started on the HF TOR Modes
by NB6Z

Can you remember the fun you had as a novice on the HF ham bands? The excitement of your first CW contact at 5 words per minute, and learning new things about the hobby as you went along? You will experience those feelings again with digital operation, and now is a great time to get your HF station going on the TOR bands! Perhaps you have recently experienced the fun of keyboard communications with the new PSK31 mode or have been a RTTY operator for years and are now ready to try a full ARQ (Automatic Repeat reQuest) mode of keyboard operation. A lot of exciting activity has taken place with TOR modes on the ham bands over the past few years! These ARQ modes have earned their place on the bands and are the only modes to ensure error free transmission of text and binary data.

The cost to get started has never been lower! There have been five or six manufacturers selling their wares to this section of the ham market for several years. With so many hams apparently willing to pay more for a slightly better mouse trap, there is plenty of perfectly good used equipment available!

HARDWARE needed to get started...

The first item you must have in a "digital shack" is a personal computer (PC). That should be no problem since you are probably sitting in front of a very good one right now! Truth is, you do not need a "very good" PC to operate the TOR modes. Any computer that will run DOS, has a hard drive and a serial port will due as a minimum. I will recommend at least a "286" with a color monitor. (You will find that many hams exchange colorful images on the air.) You probably have an old AT or XT computer in the closet at home that can now start paying you back for those dollars you spent too soon! Har Har... Of course, a newer Pentium based PC will allow you the most options.

TOR operation requires a stable SSB transceiver with fast T/R switching and a fast AGC circuit! Unless your "rig" is older than 15 years and uses tubes in sections other than the PA, you are probably ready to proceed. An older model transceiver like the Yaesu FT-101ZD is too slow for these fast switching ARQ modes. Unless you know that your transceiver will switch fast enough for Amtor, I recommend you ask the manufacturer or contact a ham dealer familiar with that model. (Obviously a new HF transceiver is a major investment. If TOR operation is not an option for you, look into RTTY and PSK31 operation as a start for digital communications.)

The only other piece of hardware needed is the TNC (Terminal Node Controller). This item is like a modem for your radio; and like the modem for your phone line, it can be internal or external to the computer. This is where things get a little fuzzy! I mentioned previously about the "better mouse trap"; well it seems that a TNC can be a little more than just a "modem". Most of these little "black boxes" contain processor units with ROM and RAM enough to do all the work of coding and decoding the digital audio signals and any thing else the proprietary firmware can claim. Actually a "dumb terminal" and some basic communications software is all some TNCs need to put you in the TOR modes properly. (Keep reading, I'll explain...) There is even some commercial software out now that will allow your "486" or faster computer the ability to operate TOR without a TNC by processing the audio via a Sound Blaster audio card!

I recommend you purchase (new or used) a TNC that will give you all three TOR modes plus CW, RTTY, Packet and ASCII in one package. Currently there is only one such model (Kantronics) and it is the one I operate; so how could I not recommend it? You should find lots of good used AEA model TNC units available which include all the above mentioned modes except G-tor. (AEA has a good reputation. It is just too bad they did not adapt G-tor to their units before they went out of the TNC business in November '96.) Look for good deals on used TNCs through your local ham flea markets and at area ham fests.

Pactor II and Clover enjoy a small but growing amount of popularity on the HF TOR bands. These units are not cheap! A Pactor II controller especially is an advanced unit for ARQ operation that in my opinion is priced well above what amateur radio operators need to pay for the enjoyment of this hobby. So why not hold off and get your feet wet on Pactor first. You may find that Pactor and the other TOR modes give you all the enjoyment you want.

SOFTWARE needed to get started...

As I mentioned previously, terminal communications software is all that you really need to send the operating commands and your QSO text to the TNC. Output from the TNC can be written directly to the screen with the same software. Communications software is not designed specifically for amateur radio operation and is not the most satisfying method. Using "Host Mode" software will interface the power of your PC with the TNC and allow you to perform many functions automatically or with fewer keystrokes. I won't go into all the details on the benefits of host software, but I will say "it's a good thing".

You can find good software to operate your TNC from your Windows 3.1 or Win95/98 desk top if you so desire. I recommend that you choose host software that works best for you and your computer by "test driving" a copy of the software first. You will want to stick with the one you chose, because learning the keystrokes of a new program is frustrating after you have become comfortable with your original software!

OPERATING on the digital bands...

After connecting the TNC to the transceiver audio input and audio output jacks, adjusting the levels, installing and setting up the host software, you are ready for what comes next! Your first link with another computer via ham radio! I recommend Pactor mode for your first time out. With the transceiver in the LSB position, tune around the TOR frequencies of the band you are operating until you begin to decode and read some of the QSOs that you find there. (Due to skip conditions, you may only receive one side of the two stations that are linked.) You will see that the QSOs go a lot like those you may have experienced on CW, only with more text. Eventually you will find a station who is calling CQ. (It is easy to detect a station who is not yet linked with another station because the data transmission is long and unbroken while the CQ is called.) When you have the other station tuned in, type in the call letters (according to the protocol of your software) and when the transmission stops, you initiate the link by pressing the appropriate key. If your signal is received correctly and sufficiently by the other station, the two TNCs will synchronize and you are now linked with your first TOR contact!

You probably will not have to let the other guy know that it is your first link! It will become obvious to him when you are not able to turn the link back to him because you have forgotten (or never bothered to read) what keystroke to use. As it turns out, the other station can do that for you from his end and so the QSO can continue. You will then find out that the hams on these digital modes are some of the friendliest on the bands! They will go easy on you while you are learning, so go ahead and ask all the dumb questions you can think of! That's how we learn! (Well, that's how I learned...)

I hope I have convinced you to give it a try! Don't let your lack of typing skills stop you. Typing is just like operating a morse key; the longer you stick to it, the better and faster you become. Have fun and see you on the TOR bands...

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