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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... |