The
Complete Bozo's Guide to HF JT65A
( a work in progress)
by Andy K3UK
Version 2.02 Last
updated May 05 , 2007 (new
/revised items appear in BLUE text)
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This
article may be freely re-distributed if credit to the author is
given
As a complete bozo, I am quite qualified to write this guide. I
have been using the mode for a whole month now and have had
"QSOs" with dozens of stations in several continents. For
example, South
Africa on 40 meters. All DX worked with low power and
a
simple piece of wire in a tree. I have no idea why the software
works but if I, K3UK, can figure out how to get it to
work.....anyone can !
If you are smart, and know more than me about this software, please
feel free to email me via andrewobrie@gmail.com I will be happy
to add your help to this document. Please let me know if I have
added anything that is just plain stupid, or wrong!
History:
The JT65A discussed in this guide is a submode within a suite of
applications collectively referred
to as WSJT . The WSJT software has been available
for several
years (2001) and was initially designed by Joe, K1JT. This
amazing piece of software has evolved to the point that there is now a
team, rather than one individual, that are developing the
software. That team consists of Joe K1JT ,
DL3LST, KK7KA, ON/G4KLX., N5HY, VA3DB, and James
Courtier-Dutton
. This team is to be commended for their contributions to the
advancement of amateur radio communications.
These non-bozos have already
written
a document that serves as a useful
guide. I have read it several times, it takes several readings
for this bozo to understand just a little. If you would like to
read the smart people's guide, you can find it at http://physics.princeton.edu/pulsar/K1JT/WSJT_User_600.pdf
The first
HF terrestrial use of JT65 appears to have been a JT65B QSO on August
14
2006 between Victor UA0LGY and Tetsu JE5FLM. The
recent explosion of HF activity began after
VE3FGU , and several of his friends, started experimenting
with the JT65B on March 23 , 2007 and JT65A on March 24. 2007.
On March 28th, several members
of the digitalradio reflector
(http://groups.yahoo.com/group/digitalradio/
) noted some unknown
digital signals on 20M and on March 30th concluded that they were JT65A
signals . The experiments of Mike VE3FGU,
Tetsu JE5FLM, David WD4KPD, Marshall W9RVG, Seli TF3AO, and
others, quickly exploded in to the hottest
HF mode for weak
signal DXing and experimentation.
What
Skills Do I Need ?
1. The ability to set your computer's clock accurately and keep it
synchronized 2. The ability to connected your
radio to a
sound card for receive and transmit (receive only, if an SWL). 4.
Able to use a computer mouse or keyboard (fingers, feet , or nose will
work just fine).
What can I
do with this software ?
This is not software that is designed for a"rag-chew" ( a
British-American colloquialism for having a long conversations) .
If you want to find out how Bert's
operation went, try PSK 31 , DominoEx, Olivia , or some other digital
mode well suited for keyboard chats. This software is for brief
exchanges of information. Mostly callsign , location, signal
report, and confirmation of the signal report. Since it is very
good for weak signal detection, it is a great QRP HF mode. You
will find the software useful for monitoring propagation and, if
you are
a DX hunter interested it a quick 5NN and moving on , this is a mode
for
you! Why not a "rag-chew" ? Well, you could,
but the software is designed for brief exchanges of no more than 5-6
words and each exchange takes one minute. So, it would take
you about 6 minutes to establish contact with Bert and find out that
the surgeon removed the wrong organ.
The software was designed for EME and Meteor
Scatter communications but I will leave that for another bozo to
write about. I have to use a spell-checker to spell meteor.
Where do I
get the software ?
They don't make it easy to
obtain. A quick trip to Google will
give you several dead links and even a visit to WSJT "Smooth Jazz" , an
FM station in Florida. We want "jazz" of a different kind,
so go to http://physics.princeton.edu/pulsar/K1JT/WSJT597.EXE
for the most recent version. If you have a REAL slow computer,
there are older versions that will work well, check http://physics.princeton.edu/pulsar/K1JT/Download.htm
for these. DM780 a digital mode
companion to Ham Radio Deluxe and FLDIGI, a well known Linux
application,
are both reportedly working on adding JT65A.
Installing
the software:
Assuming you remember
which folder you downloaded the
software to, go to that folder and click on the
WSJT597.EXE file. The install will default to your program files
folder and the usual path will be c:\program files\wsjt\wsjt6.exe
. Once you have done this, boot up the program. Take
a deep breath, prepare to be confused and amazed.
Setting Up
The Software:
This should take less than a minute . When the program boots up, you
will see a brief dos-type window pop
up.
Ignore this for a while, it s a useful window but something you may
never need to pay much attention too. A few moments later
you will see the WSJT main screen. Don't panic if the
"waterfall" is dark and devoid of signals , this is normal at this
stage. Click on MODE and select JT65A.
Here is what you will see when the main window opens up .
Ignore the bit about the moon unless you are thinking of a moonlight
walk with that new girlfriend, or plan to bounce radio signals
off the moon. Yeah right...like that's really possible.
Now, we will set it up for your callsign and your location. To do
this, you need to click on SETUP and then select OPTIONS.
You will note that in this picture, the callsign is already set-up for
K3UK. This may come as a complete shock to some , but you
are NOT K3UK. Your government issued a call sign just for
you. In the box named MY CALL, enter in your call
sign. Next you need to figure out where you are. This may
not be easy if you have just drank two bottles of your favorite grog,
or have traveled two days in a row boat to that rare DX island.
However, those that do know where they are located should try to know
their GRID LOCATOR and then you place your grid locator in , you
guessed it... the box called GRID LOCATOR. Since you are a
complete bozo like me, you may not know what your grid square
is. Grid locators can get very specific, to within a few
metres. For JT65A HF work, you really don't need to be that
precise. The grid square for your post office or town centre will
do. Americans can go to http://www.arrl.org/locate/locate.html
. Britons can go to http://www.aber.ac.uk/cgi-bin/user/auj/locate.pl
. It may be hard for some American and Britons to
realize , but there are other countries in the world. That is
good , because we need other countries to make DXing more
exciting., and provide places to go on vacation. If you
live in one of these other places , try
http://www.qsl.net/ad7db/yourgrid.html.A
new alternative is F6FVY's
Google Maps server that allows you to find your location on a Google
map and your grid square will pop up on the map. Checkhttp://f6fvy.free.fr/qthLocator/fullScreen.php
. The WSJT software does not require grid locators but the
grid
locators are used in the default mode instead of an RST report.
Setting
the Radio for Transmit
OK, so you have entered in your callsign and location. If
you want to make the software key your radio when transmitting, you
need to tell WSJT which comm port you are using for "PTT".
My station uses a virtual serial port , port 5. You will
likely use 1, or 3 if you are using a regular serial
port. Enter your port where it says PTT PORT.
Just one more thing to do. The software can calculate the
distance between your grid locator and the received station's grid
locator. Most sensible folks use metres but a few people clutch
to a old system referred to as "miles" (mainly those Brits and
Americans, again). Remember, I am a complete bozo, so I use
miles. Click on the ML or KM in the DISTANCE UNIT area.
That's it. Leave all the other stuff alone.
Receiving
signals :
Assuming you already have the audio from your radio receiver connected
to the input of your sound card, you are close to being ready to
receive. Remember though, the software was written by somebody
completely intelligent. There are many useful things that can be
done with the software, the smart author thus decided that
the receiving of signals needs to be activated. Your WSJT
main screen should now look like this.
Note that I have highlighted a button called MONITOR. Note also
that the other area I highlighted has your callsign and grid square
inserted. Now, click on the MONITOR button with your radio
tuned to any HF frequency and you will eventually
see signals on what looks like
a waterfall. I say eventually, because this
waterfall is one thoughtful waterfall. It needs to think a
while about what it is receiving and then, precisely when your
PC's clock signifies the start of a new minute, the display will come
to life with some interesting squiggly lines. Assuming you
see some squiggly lines , you are in good shape and ready to move
on. To be honest, this
"waterfall" is not a waterfall in the traditional sense. The
waterfalls that you see in Digipan, Multispsk, fldigi, MMTTY,
Winwarbler, DM780, MixW, etc etc, display the signal on a
continuous basis and indicate the intensity of the received
signal. This display in WSJT actually takes a snap shot of what
you have received in the past 48 seconds and displays it all at
once. The moon-bouncing meteor dodging hams that use the
WSJT software, use this aspect to analyze minute details that
enable them to determine if the Martians have actually entered our
ionosphere. It is an important "main graphical area" ( as the
official guide calls it) , even for HF applications. More
on how to interpret this later.
Frequencies
:
We might as well get the radio
tuned to frequencies known to be used
for JT65A on HF. Remember this is a new application for the
software and it is still evolving. The most commonly used
frequencies are 14075 to 14076 ,7075 7076 in North America
,7042 to 7043. 7025, LSB for Europe and Oceania, 3576
(North
America ) , 3796 (Europe) ,
also 18102, 18106, 10147, 21076,
24910 . 1805 to 1808 . 14076 or 7076 are the best places to
start. These
are DIAL
frequencies, most
use USB but there are some that
use LSB. By far the simplest method of figuring out where
the action can be found is to use your web browser and go to http://www.chris.org/cgi-bin/jt65talk
. This web site is the place to go for announcements of who is
active and what frequency they are using. The website is
maintained by Chris, N0UK . Yes, he is N0UK and I am K3UK.
We are both part of a British plot to take control of the JT65 world
and lay the foundation for re-acquisition of colonial America in
2076. The Queen visiting the Kentucky Derby is also
part of this plot.
So tune to one of the above frequencies , get a cup of coffee and
relax for
a minute or to.
Tuning
Accuracy :
Now, some important stuff. The smart JT65A users will eventually
point this out to us bozos, so I figured I will tell you now. The
software decodes signals over a wide range, up to 600 Hz. So you
can decode several signals within this 600 Hz range . You can be
decoding all of them but if you transmit you could be several
hundred Hz from the other station's transmit signal. This , to
the JT65A afficinados, is a crime and war crime tribunals may
get formed. Even a bozo like me can understand this after a
while. It's like working "split" and taking up more spectrum than
is needed. It is also like not being zero-beat in CW and trying to work
a person who has a 200 Hz filter active. If you are 300 Hz from
his frequency, he is not going to hear you. Don't fear,
this is easy to address, more on this a little later in the
document..
Let's not worry about accuracy at the moment, lets just tune a
signal. After a few minutes on an active frequency your
main screen may look like this
The blue highlighted text is my work, your screen will not
automatically highlight text..
What the heck does this mean? Smart guys already know, but bozos
like me are still learning. It tells you that at 1635
(and zero seconds) the software decoded DK70M responding to
DL5SWB. Just like a regular phone contact "P5DX de K3UK".
. It also tells you that DK7OM is in grid square JO53 .
This string of information also tells me that the dB was
averaging -7 during the minute or so the software was decoding DK7OM's
signal . This is a signal to noise type of reference. 7 dB
in to the noise. This is a good signal, WSJT will decode signals
well below -20 dB. The minus 73 under the DF area tells me that I
am close in frequency , about 73 Hz off, good enough for now.
I'll save the other info in that string for a later discussion.
What About
The Rest In The Window. ?
The
"RO" RRR"
and "73" are just snippets of a conversation used to confirm the QSO.
Its like tuning in your radio and hearing someone say
"Roger" or "73" . More on this later. Version 5.9.7
has an option that suspends use of the RO , RRR, and 73 messages.
This option was specifically added for the new HF application of
JT65A. The RO , RRR, and 73 messages in the default format were
designed with EME and Meteor Scatter QSO in mind and are as brief as
possible. For HF application of JT65A, the need for very brief
bursts of information is not paramount., so the new version has added
an option to include callsigns and signal reports . The RO , RRR,
and 73 messages are messages in a special format and can be decoded and
even weaker signal levels that the other messages. So when
signals are very weak on HF you may still see these messages.
That Weird
Waterfall Thingy :
As mentioned earlier , that weird waterfall thingy (the "main graphical
display" ) can tell you a lot. The rookie user needs
to know a few basics that will enable you to be closer to the received
station's frequency. In the picture below you will see a red
spike on the spectrum display.
You can take your mouse and click on the red
spike (see center of picture above) and that
will get you close to the right frequency. The peaked
blue spike tells you something useful too, I will add that at another
date.
Those RRR and 73 reports
that are decoded will show up as orange or purple lines on the
waterfall.
Reportedly,
clicking on the purple peak will also serve as
an tuning aide, I have not tested that yet. For meteor scatter
and EME work, the orange, purple, and green lines can be valuable in
digging out a signal. For JT65A on HF, they are not as important.
Using a "waterfall" l that has
to think for a minute before it updates
information can be frustrating. Don't worry, the author has
another trick up his sleeve, a second waterfall! This is a
REAL waterfall just like the ones Peter Martinez and Skip Teller
invented for use old PSK31 users. Click
on
VIEW at the top of the main window and then select SPECJT. A
real waterfall will open up (if you are using an older
version
you may need to manually boot up "spectran.exe" for this ). This
waterfall can detect RF
generated by a flatulent butterfly 1000 kilometres away.
Eventually you will stare at this waterfall and see the tiniest hint of
a signal and be amazed as the software decodes information from
it. Note on the picture below, you will see this second
waterfall, a received signal and the mouse cursor indicating
tuning the signal to the sync tone. For HF work, this
second graphical display will be the most important display for
identifying the presence of a signal and in accurately tuning in the
station.
Clicking
with the mouse, on the longer sync tone will get you very
precisely tuned. The sync tones are actually 1270 Hz, you and your dog
should have no difficulty learning to recognize the sync tone both in
the SpecJT, and via your ears (actually, your dog may have
difficulty
understanding the waterfall display, sorry to point this out ) .
The authors of this software think of bozos like me and actually send
the sync tone quite frequently, so you get lots of chances to spot
it. If you have monitored the active HF JT65A frequencies you
will have heard a few JT65A signals. These tones sound a little like
the old Throb mode, and a little like very slow DominoEX. This
throbbing type signal actually sends the important sync tone about 65
times in a typical sequence, the other tones in a sequence are sending
information. The tones actually change a little during a "QSO",
and some of the messages actually don't use the sync tone in the same
way. That's too complicated for a bozo's guide, but the
aforementioned smart people's guide explains it well. . The
general rule of thumb, detect a
signal within the SpectJT that looks like JT65A and click on the LEFT
edge of the signal. Be aware that the SpectJT will display all
kind of other signals within the range of the waterfall , so you may
see PACTOR bandits, PSK Rangers, RTTY rompers, Hell raisers, and a
plethora of other digital modes. JT65 is fairly easy to spot
after a couple of attempts, the only other digital mode that looks a
little like it in the SpectJT is MFSK16, but this sounds very
different.
The
signal in the picture above is a very weak signal.
Sometimes
just a very very slight line has shown in the SPECJT waterfall
and I have successfully decoded a signal. Remember , you don't
need to be that precise to just decode signals, you need to get precise
to be transmitting as close as possible to their transmitted
signal. The reason you want to be close is because
the
smart
JT65A operator my not want to be receiving signals more than a certain
distance from his transmit signal. He may have , for example, set
the software to ignore signals from more than 200 Hz away from
his signal. So, if you are 300 Hz away, he will never decode your
signal. I often listen with a 600 Hz range so that I can
get a sense of who is active on the band , but switch to 200 Hz
when trying to have QSOs. To set the range , left click on
the number in the TOL box to raise the setting, right-click on the
number to lower the setting. Click the "freeze" button to
maintain this .
Remember
to raise TOL to 600 and Freeze "off", if you are just looking for QSOs.
While the
SpecJT window is open , click on OPTIONS and select JT65
DF Axis. This will help further in precision tuning.
While there, you can also play with the palette settings and vary
the
appearance of the waterfall. There will be a few occasions where you
cannot even see a signal even in this highly sensitive waterfall.
The different palettes will make it possible to see extremely weak
signals , try "hot" for example.
Note at the bottom of SpectJT
there
is a "gain" area , just to the right of the digital clock. You
can adjust the gain of the waterfall with this control. You can
also adjust the brightness and contrast of the SpecJT waterfall.
Try that, if your ears detect a signal but you don't see it on
the
waterfall. The gain
control can be an important factor if
you experience a situation where you are unable to decode signals,
please see the "trouble" section of this document.
A good
Bozo's guide should be short and sweet, but I need to explain a few
more useful tips about receiving a signal . Take a look at this
The stronger signal at the bottom right-hand corner is VE5MU. The
weaker signal is K4CML. They are working each other but not
exactly on the same frequency. Their QSO copied at my station
shows....
Pretty close though and will work unless they have their TOL set to
less than 100.
Now take a look at this
VE5MU and VE7TIL copied at my station on 40M, both almost exactly tuned
with each other. My station recorded their QSO
024800 9 -7 1.5 -121 3
# VE7TIL VE5MU DO70
OOO 1 0
024900 3 -9 0.1 -116 3
# VE5MU VE7TIL CN89
OOO 1 0
Although -121 and -116 DF from where I was tuned, they were within 5 Hz
of each other.
Please note, the callsign in the above pictures do NOT appear in the
SpecJT, I added them for illustrative purposes.
I am sure
you
wonder what all the other numbers mean, this will
be added at a later date but it is worth mentioning that the last
number in the line (the zero as in "
1 0 " ) is an
indicator
of how confident the software is that it has decoded
correctly. The software is quite sophisticated and sometimes acts
like a human ear/brain, it guesses what it heard. The confidence
scale goes up to 10 , supposedly anything under a three is
questionable. I'm still trying to figure out what most are given
a zero but even when obviously accurately decoded.The smart author of software,
Joe W1JT, took pity on this bozo and sent me the following...
"You mention the twonumbers at
the end of each line of decoded text. If the first of these is 1,
it means that "Deep Search" was not required and decoding will nearly
always be 100% correct. If the first number is 0, the
second (some number between 1 and 10) gives an indication of relative
confidence of a Deep Search decoding. Since the default list of
"plausible" callsigns is VHF/UHF and EME oriented, Deep Search will not
be very useful on HF unless the operator becomes fairly sophisticated
in using WSJT". Deep Search has no relation to
Linda Lovelace and has apparently no connection to the Deep Throat that
did Nixon in. In is a software function designed to help the
moon-bounce and meteor scatter hams find fragments of RF and
match the fragments to known users of the software. It is
recommended that you turn this feature off in the main graphical
display area , by going to OPTIONS/DECODE/JT65 and then checking "no
deep search" . Leaving it on does not cause global warming
but does, on occasion ,cause a "phantom signal" to call you. If
you see a call to you when you have not been transmitting, it is
possible that Deep Search caused it.
One more
item on receiving...
In the SpecJT waterfall
you will notice a receive noise level indicator in
the lower right-hand corner. It displays the noise level in dB. I
have been
told that things do not decode very well if you have something like a
4-5 dB level (above zero, not below) . I have also noticed
that it does not decode very well when you have a very low figure, like
-20 dB. A number of factors can influence this and the noise level will
change from band to band. The biggest single factor will be
whether you are getting enough , or too much, audio from your radio to
the input of your soundcard. Many digital mode interfaces
like Microham or Rigblaster products have knobs that control the audio
levels. If your RX noise level is too high or low, adjust
the audio so that your noise level is around 0 db without a signal
present. Smart people have also
suggested it works better with AGC off, play around and see. You can experiment with your
rig's filters,
noise reduction circuitry, AGC settings , RF gain settings , etc,
etc.
Transmitting
Signals/Having A QSO.
I've
said this three times already but... to transmit you first need to
understand that the smart JT65A guys all
expect you to transmit at a certain time. That time needs to be
synchronized, so synchronize your PC's clock with Internet time or
WWV. I use an application called Dimension 4 that keeps my
clock synchronized. Why? Because the
software needs time to decode your transmitted signal and also switches
to transmit at certain times. If your timing is off, the other
station may have already switched to transmit and thus not decode your
signal , or their decode period would be so short that it did not get a
chance to decode all your information. You can get the freeware
Dimension 4 at http://www.thinkman.com/dimension4/download.htm
Transmitting
Frequency.
Popular digital mode
software like MixW, Multipsk, MMTTY, have functions that
maintain a relationship between the received and transmit
frequency. These functions, often via a "net" on/off feature,
cause the radio and/or soundcard to adjust when you click on a signal
in a waterfall. The WSJT software has a similar function and is
labeled in the main graphical display as TxDF= . In the
older versions one had to always match your transmit and receive
frequency manually. It may be useful to first understand how to
do this, and then learn the new TxDF= feature. So, lets
begin an manual reception and transmit.
Here we see a CQ from P5DX
, my radio was tuned to 14076 USB but my eagle eyes (and bat-like ears)
spotted a signal further down the waterfall. I clicked on the
left-side of the signal on the SpectJT waterfall and the green
scale markers shifted to show that I am tuned about 500 Hz below where
I started. Although working North Korea is becoming routine for
me, I take pity of the poor guy and decide to work him once
again. If I just transmit, my rig will transmit at the zero
mark, 14076 USB. He is 500 Hz below, at 14075.500. So
all I really have to do is manually turn my dial 500 Hz lower, to
14075.5 and then...
Here you can
see the old received signal shifted 500 Hz to the left and more
importantly the new receive frequency is close to my transmit frequency
at 14076 USB. Simple , right?
To get more adept at precise
matching of the received frequency and transmit frequency, use your
mouse to move left and right on the SpecJT waterfall. Note
how the frequency and DF changes.
Mouse pointer at 881 Hz
and 388 Hz below transmit frequency.
What
About This New Fangled "TXDF=
feature?
Not only am I a complete Bozo, I
can be a little mean. I threw the word "fangled" in here
just to puzzle the folks that bring you the Russian and Spanish
translations of this document. I think we should
offer a prize to someone who can tell us the origin of the word
"fangled". Anyway, I deviate from the mission at hand. Actually "deviate" is a
key term for this section of the guide. When you tune a
signal and successfully decode it, the decoded text will tell you how
far your tuned frequency is from what will be your transmit
frequency. For example , this decoded text
035100 10 -15
3.4 -160 3 * VK7CAV
N5BO
-16
1 0
Shows that the DF was 160
hz below where my transmit is set. The very smart author of the
software has now enabled us to match the receive and transmit frequency
instantly via a simple double left-click with your mouse.
TxDF set
to default
zero
TxDF adjusted 98 Hz and matched
To do this, locate the signal in the
SpecJT, aim your mouse on the left edge of the signal and double click
on it. Now single left click on the TXDF and the deviated
frequency will be indicated You , despite being
a bozo, will have achieved something akin to to mastering rocket
science...your transmit frequency and receive frequency will
match! Now, actually the smart author is doing this via having
the software fiddle around with the capabilities of your
soundcard. Your radio is not adjusted, don't worry about that
"split" button being activated or, God forbid, that RIT thingy
being turned on !
A word to the
wise. Users of some RTTY or PSK31 software might be used to
the fact that once you have instructed your software to match receive
and transmit frequencies, they stay matched even as you re-tune and
work stations on other frequencies/bands. This WSJT software requires
that you make the adjustment each time you are going to transmit ,
assuming the station you want to work is on a different frequency than
the one you just worked. For example, suppose you worked a
station that had a DF of 233 Hz. You left-clicked on TxDF and it
matched your settings so you were exactly on the same receive and
transmit frequency. Now that you have worked the station, you see
on your screen that KT2Q has been decoded with DF of -321 Hz. You will
need to again click on the TXDF button for it to match the DF , before
you transmit.
Audio
levels:
As with any digital mode that relies
on your PC's sound card, you need
to pay a little attention to the quality of your transmitted
signal. Typically, when using modes like Olivia or the old PSK31,
people suggest you keep your ALC level to the very minimum. One
of the non-bozo types emailed be recently and suggested that the nature
of the JT65A signals is such that you don't have to worry about this as
much , and can give a good amount of ALC. I still keep mine
fairly
low, old habits...
Another
friendly ham reminded me that this mode is full duty cycle and he
suggested that people should not use full power for long periods.
This mode does not need a whole lot of power. A ham , Tony
KT2Q, popped up one day and said he had a "Bird meter in
line". Being not only a bozo, but a British bozo, I
wondered whether a bird meter was something similar to "a chic
magnet", perhaps ? Maybe it can detect the fairer sex at a
thousand paces ? Well , it turns out that this KT2Q guy is one of
them non-bozo hams. The bird meter had a "plug" in it . So does
my bath tub, but the bath tub does not help with most of my radio
projects,. Well the "plug" enables him to calibrate his radio output
and accurately determine how low his power is . I was able to
detect and decode his JT65A signal when he was using 250 milliwatts on
40 meters. Another ham, some 600 miles away from KT2Q, was able to
detect him below 50 milliwatts. So, you don't need to
have your transmitter set for high power. I often run just 50
watts on 20M.
CQing.
If you want to CQ, you have to decide whether you want to transmit "1st
minute" or "second minute". This helps to maintain world
peace and keeps QSOs orderly. "First minute"
means 00 and any even numbered minute 02 , 04, 06, and so on.
Second minute means 01 and any odd numbered minute , 03, 05, etc.
So, if you were transmitting a CQ on the first minute, you should set
the main window to TX 1st and select your CQ message. You
should also use the auto transmit method. As illustrated below.
At the
precise minute, your rig will transmit. It will send the
CQ for about 48 seconds . You then will wait until the
beginning of the next odd numbered minute and , if lucky, you may hear
or see a signal responding to your CQ. Please be aware that you
may NOT see a signal in the SPECJT or hear a signal with your
ears but may actually
be decoding a signal. After about 50 seconds in to the
minute, a blue decode button on your screen should be active
and around 55 seconds ,or so , any decoded signal will pop up on
the
screen. On my slow computer, the decoded signal sometimes
does not pop up
until several seconds in to the next minute . This can be
annoying and confusing, so if this happens to you turn on QUICK
DECODE and the decoding process will start about 5 seconds
earlier. You will then get the decoded text in time to read the
information before your next transmission. To turn on QUICK
DECODE go to go to DECODE in the main graphical area, select JT65, and
then Quick Decode as illustrated below
If
,after CQing, you
receive something like this
. 171500
0 -7 -0.1 471 3 It probably
means no one responded, or your rig did not hear anyone respond.
This is essentially random noise.
If you
received something like this ... 165200 10 -11
-0.2 -27 5 * YOURCALL
WQ5S EM13
It means WQ5S
heard you and is responding with your callsign , his
callsign, and his grid locator which serves as a
report (they may also respond sometimes with and R and a number instead
of a grid square, this is a signal report) Here is an
actual example..
Lets pretend
you are VE5MU (haven't we all wanted to be VE5MU at some
point in our lives ?) You called CQ, WQ5S answered.
Now what the heck do you do ? The new version now gives you a
choice of what responding message format you can use. If you
left-double click on the callsign of WQ5Q you will see
Some
standard messages have incorporated your callsign and his callsign
automatically. However, the new recommended format for HF use of
JT65A is that you access a different message set. Instead of
left-double clicking on a received callsign , RIGHT-double
click. At my location this causes a 20% increase in carpel tunnel
syndrome symptoms, but hopefully all it causes at your house is the
following.
Note, I have
now switched from using VE5MU as an example to using
UA0AET. In the above box, you will see that it
not only copied the callsign of the other station when I right-double
clicked, it also copied the signal to noise ratio which is illustrated
in the TX2 and TX 3 boxes . In this case it is -7dB, a good
signal!If you used the
right-double click maneuver, you should note that the Auto-ON
button has turned red. This means that your radio will begin
transmitting automatically at the top of the next minute.
Since you are the station calling "CQ", you most likely would have
already selected auto-on.
Before each
transmission, you need to determine which of the possible six
messages you will be sending. Obviously, if CQing, you will
select TX6. So, if P5DX in North Korea has heard your CQ and has
responded with :
VE5MU
P5DX PM27
Now what the
heck do you do? Well, just like in most other amateur radio
modes, you respond with his/her callsign to let him know your heard
him/her. You also respond with a signal report. Under the
new "HF enhanced" version of WSJT-JT65A , you would respond withTX3 which is... "P5DX K3UK R-7"
P5DX would
then send his report as ...VE5MU P5DX RRR (TX4)
You would
then respond with either message TX4 also or some operators just skip
to message TX5 and sent the 73.
P5DX may also
send 73 but it is not required.
All of this
assumes you are hearing each other well. Suppose you got the
first couple of messages, but when P5DX took his/her minute to confirm
your report with RO, you never received it. The convention is
that you just send your previous message again. P5DX will receive
it again (hopefully) and realize that this means you did not receive
his RO. He will send it again and , if you copy it this time, you
will send..... This format can be repeated for any of the
message stages .
Writing this down in a Bozo guide can make it more complicated than it
really is. Remember that smart bloke that wrote the
software? A dude called Joe. Joe is so smart that he
stuck simple way of helping us bozos right in to the software. If
you hold your SHIFT key down and press the F5 key at the same time, you
will see something like this ...
Actually, I broke it down for us bozos. The chart above explains
the newer method intended for HF use under fair to good conditions.
Alternative
Message Format
As mentioned
earlier, the new HF enhanced version should work well for most HF
conditions. However, you may run in to some "old timers" who use
the older method, or find someone using the older "short hand"
messages because they can be decoded better when a signal is very
weak. So, it may be useful for this Bozo's Guide to
explain this message format too.
The
author's chart best illustrates this:
Don't ask me what the OOO actually stand for, but this exchange means
that you have received WQ5S' information. If
WQ5S received your 000's, he will respond with simply with
RO, no call
sign, just RO. This means he has received your 000's. After
you receive his RO, you send message number TX4 by
selecting it before your turn to transmit arrives. TX4 will
transmit at the top of the minute and send RRR. Again, no calls
signs, just RRR. This means you have received everything for a
valid QSO, : A valid QSO consists of his callsign , the fact that
he has your call sign correct, the acknowledgment that he
received your OOO's . He will send you RRR to let you know that
all is correct his end. Often, you then send the message number
TX5 with a 73 in it. Some people type in extra info in this
messages like
73 TU good night ur best -7
db.
This is optional an usually is typed in to TX1, message number 1.
This will sounds confusing but after a couple of contacts
you will have it easily figured out. If you did not receive the
acknowledgment of the OOO's or an RR, just resend and hopefully you
will get it the next try.
Remember,
the team designing the software are
not
bozos, they are smart blokes and their inventiveness is extremely
helpful to us bozos. In their cleverness, they designed a mode
that actually changes the nature of the digital tones depending on what
is going on in the QSO. This is almost like switching from SSB
phone to CW in the middle of a QSO because you want to make sure your
weak signal got through. In JT65A (and other modes in WSJT)
a CQ message , TX1, will appear differently on the SpecJT
waterfall that other messages. The RO or 73 message will appear
different too. Let's take a look at the picture below
Short Hand Message in older format and for
WEAK signal decode
(I have RRR confused with RO , I
will re-do this graphic later when I get a better capture , but it does
basically illustrate what
you need to know)
I have
illustrated , in the above picture, the typical patterns you will see
in the SpecJT. With a little experience you will be able to
visually SEE what is going on in a QSO , and know which part of the
exchange is taking place. You will also be able to HEAR the
difference because the tones sound different to the human
ear. Knowing what the different stages (messages) of
a QSO sound like, can be useful when working weak signals in a
pile-up.
You will note
that the CQ signal is quite distinctive, much wider than the short-hand
messages.. Some people
get confused by the fact that the RO , RRR messages appear without a
call sign. Was he really coming back to me? It is
confusing, that is why K1JT revised the software and added the new
message formats that can be accessed via double right-clicking on a
callsign. These messages have callsigns throughout and avoid the
confusion.
However, the nature of these "shorthand" messages is such
that
they can be decoded a further -5dB in to the mud ! This can make
the difference between working that rare DX station or not.
Some people will send you a message that says
something " Best -18 TU 73". These smart people
are manually typing the message in to the TX1 message text box
and sending it instead of the optional TX5 message. Since it is
sent after a QSO has been validated by RRR, it is perhaps not
that essential that the message get through, so they use the
wider
, less robust, TX1 message.
N4WO is CQ on the first minute ( 1828, 1830, 1832, ) and DK7OM is
transmitting the second minute (1829 and 1831) .
Both are within 61 Hz or so of each other but are not hearing
each other. If you want to work them, you have a choice.
Who do you want to work ? The new HF enhanced version makes the
choice a little easier. If you want to work N4WO there are
three things you need to do..
1. Determine which minute N4WO is transmitting.
2. Set the
messages group with callsigns and signal report. 3 Match the
received frequency with your transmit frequency
Setting
1st or Second Minute : In
the above example, N4WO was transmitting at 183200, 32 minutes
past the hour, and even numbered minute. This is the first
minute, so you need to unchecked the TX1st box so that you transmit the
second minute. You will do this just once at the beginning of the
QSO. The second minute sequence will be maintained throughout.
Setting
messages group with callsigns and
signal report.: If you wanted
to work N4WO you would have seen something like...
183200 9 -13 0.4 -124 4
* CQ N4WO
EL88
1 0 Right-Double click will populate the message
groups with the callsigns and signal reports..
Matching Received and TX Frequency:
After you have selected N4WO , above, you can then double click on the
signal in the SpectJT (or on the red spike in the main graphical
display ) and then click on the
TXDF button. It will turn red and the frequency deviation will be
shown. Using the above example, it would read TXDF= -124 .
That's it, you are matched!
So, at the top of the minute, your rig sends TX1 , which
is N4WO VE5MU DO70
N4WO receives this information and now knows that you are calling him
and his signal report is -13 db.
He sends TX2.... VE5MU N4WO -8
He is letting you know that he is receiving you with a signal to
noise ratio of -8 dB.
You then send... N4WO VE5MU RRR or the 73 message.
This tells N4WO that your received his R-8 report and that you are
"rogering" the report. N4WO will like this because when he
receives "RRR" or 73 it makes his contact official. He may
reply
with another RRR, rogering your information or he may skip straight to
a 73 message. "VE5MU N4WO RRR" or "VE5MU
N4WO 73"
So, the QSO is "good" now that you have received his "RRR" or "73"
.
Instead of TX5's basic 73. Some folks get a little fancy and send
a brief message , perhaps like "Tnx John 73". This is usually
done by typing the "Tnx John 73"
in to the message box TX1.
You will notice that when transmitting, the message box you have
selected changes to a certain color. More on this later, it just
signifies what type of message you are sending. I am mentioning
it here because some new users panic when they see the message box turn
RED. Red does not mean your rig is about to explode, it does not
indicate anything bad at all!
OK,
I just
worked North Korea on 160M, where do I log it. ?
Clicking on
the "log QSO" button will log the QSO but you will need to first tell
WSJT which band you are on, the software does NOT read your radio's
frequency. To do this, click BAND in the main graphical display
and select the band. Note, the bands are labeled via Frequency
not wavelength. e.g "14" is 14 mHz or 20 metres.
You can view
the log by opening the log.txt file with a text editor , like Wordpad
or Note pad. log.txt can be found in your main WSJT folder.
In the folder
there is also another interesting text file, called all.txt. This
tells you knot only who you log but who you received and when you
transmitted. e.g.
I've
worked a lot of JT65A and am not getting the same high anymore, is
there a more potent drug?
The bigger "high" can be gotten from EME or Meteor Scatter
operations. Once addicted to this, you become known as a Ping
Jockey. See http://www.pingjockey.net/cgi-bin/pingtalk
for more on this addiction.
Trouble
:
Remember that "DOS-type" window that I told you to ignore at the
beginning of this document. This can actually tell you if there
is a problem with the sound card device or if your PTT circuit is not
open. If you suspect a problem of this nature, log on to http://groups.yahoo.com/group/wsjtgroup/
and ask for help their.
Soundcard
Clock
If you have
an obvious JT65A signal that you can hear and the waterfall sees but
it is NOT decoding, you may want to make sure your soundcard clock is
accurate. Most digital software like MultiPSK,
MixW, and Winbarbler,
have features that will enable you to adjust your soundcard and keep it
accurate. The WSJT software displays your clock rate
as highlighted below
You want your
settings to be around a 1.0 .
It appears
that WSJT also can adjust the soundcard rate, check the SETUP/OPTIONS
/RATE IN /RATE OUT area.
Audio
Levels in to the Soundcard
As mentioned earlier in this document, you may experience problems in
decode if the audio level is too strong or too low. You can lower
or raise these values first with the Gain Control slider in SpecJT and
additionally with your soundcard line-in control mixer.
With no signal present, -2dB seems to be a good level. These are
not always critical but if you cannot decode an obviously clear signal
you might want to make sure you are not in the -20 dB or + 20 db
range. See below for key areas in control of the audio level.
If you cannot get enough audio from your rig to the PC soundcard,
consider using the MIC-IN jack on you soundcard. Be careful not
to put TOO much audio in to your soundcard.
Acknowledgment:
As a complete bozo, I needed
help understanding things, Thanks to
all that responded to my questions in the first few weeks of
learning. Thanks to
David WD4KPD, Tony KT2Q. Chris, N2YYZ,
Steinar LA5VNA, Mike VE3FGU, Colin K4CML, John
VE5MU, Bill N9DSJ, George G4PCI, Bruce,
N5SIX, John W5UBW, Walt K5YFW, Scott VE7TIL, John N2JH, Al
WB7SWW. Marshall W9RVG. Joe K1JT. More to be added soon.
Other
Guides by Andy K3UK
The
KB2EOQ Quick and Dirty Guide to PSK31 (2000) The KB2EOQ
Quick and Dirt Guide to Digital Modes (2001) The Quick and
Dirty Guide to Kenwood D700A and Digitraveller GPS Unit First English
Help File for MMTTY (very old) The K3UK
Quick and Dirty Guide to Chip 64/128 Communicating
with PSK31 (in Logger16 help files) Interfacing
Your Radio (within Zakanaka and Logger16/32 help files)
