The Quick and
Dirty Unofficial Help File for Nino IZ8BLY's Chip 64 Software
By Andy K3UK
This is a temporary English language help file for this new
amateur radio mode, intended to serve until an official version is
released. For more information on the mode, please consider
joining the Yahoo Group dedicated to this mode at http://groups.yahoo.com/group/chip64
or the Digital Radio reflector at http://groups.yahoo.com/group/digitalradio/
If you are a member of the Chip 64 Yahoo Group, a detailed
description of this mode is available in the FILES section
is it ? A digital mode
for amateur radio communication. It is a phase shift keying
application that utilizes some spread spectrum methods.
do I get the software ?
and download the file. Install on to your computer.
do I make it work?
We will assume that you already have a amateur radio licence
and suitable transceiver that is connected to your computer via a
suitable interface. If you do not, please go to http://www.qsl.net/wm2u/interface.html
for basic instructions on how to connect the output of your computer
soundcard to the input of your transceiver, and the output of your
transceiver to the line-in of you soundcard.
Assuming you have your radio and PC interfaced, getting started with
Chip 64 is easy. Boot up the software and you will see a
screen ...illustrated below (I will make a better screen capture at a
I may add some graphic
illustrations of certain task, later when I get more time.
the software to control your transceiver: Your
radio will need to "talk" to the Chip 64 software and cause it to
key/un-key your radio as you alternate between transmitting and
receiving. To do this, you need to click on the WRENCH
(Spanner) ICON in the upper left top of the screen. When you do
this, a dialogue box will open and you will see several options.
Click on PTT PORT. Choose a Comm Port that you wish to
use. Chip 64 works well via regular comm ports and virtual USB comm ports
such as those used by Microkeyer.
in your callsign and other personal information:
Next, click the Wrench Icon again, this time choose General.
Enter your call sign and personal information in the spaces provided.
Setting up a few Macros (or
"buffers") : While Chip 64 is a slow-typist friendly keyboard
board mode , you can save yourself some time and effort by
pre-programming some macros with personal information. Chip 64
already comes with a some general content for you to use. I
would suggest you check the macros at the bottom of the screen by
RIGHT CLICKing on each one and adding your personal touch. The
average user will want macros them to at least include CQ,
QRZ, Station Information, Name/QTH, and one I call a
"RETURN" macro (simply mycall de their call , or in Chip 64
syntax : $OTHER de $QRZ )
If you make a macro that you wish to also handle the automatic
switching from transmit to receive, your macro should end in
Nino IZ8BLY is the author of other amateur radio software including a
MT63 application called Stream. In Stream, he appears to
use the same syntax for macros that he uses in Chip. Therfore, it
appears logical Stream macros will work in Chip . They are;
Text sent / action taken
The station callsign (as
typed in the Preferences window)
The other party's
callsign (defined with F11 key)
Sends standard CQ call
Time stamp (UTC time)
Time stamp (local time)
Date stamp (referred to
Date stamp (referred to
The dollar sign
(otherwise not printable)
Sends ASCII character
number nn, e.g. $c65 sends "A"
Sends text assigned to
the user definable button n (ranges is from 1 to 12)
Clears other party
Sets the output power
level (soundcard volume) to n.
The value ranges from 0 (silence) to 255 (full volume).
This metacommand influences the mixer setting.
Closes the transmission
and goes in RX mode
The signal report of
other party measured on last transmission. The values is in S scale as
for transceivers (0...9, 9+5...9+60)
The best measured
confidence percentage of the last
Thanks to Ron W4LDE for this information.
I've set up my rig, computer, and programmed in my call sign, now what ? Well,
there is not much more but perhaps you should double check which MODE
you are in. Chip 64 usually defaults to Chip 64 but you can also
transmit/receive Chip 128. Most people use Chip 64, so I suggest
you start with this. Go to MODE in the upper left of your
screen and make sure Chip 64 is checked (ticked). While there,
check to make sure UNCLOCKED DECODER is checked. Most
people seem to use the UNCLOCKED DECODER although some users start QSO
in difficult conditions with a CLOCKED DECODER.
CHIP 64/128 . :
While there is A LOT to
this new mode, there is not much more you need to do other than get to
experience the mode in action. Turn your radio on, if
you have it interfaced correctly you will see graphic evidence of
received radio signals, or atmospheric conditions, via the
WATERFALL that is towards the bottom of your screen.. The
default Chip 64 setting appears to be such that received signals appear
as white vertical lines on the waterfall. I suggest that you tune
your radio to a known active PSK31 or CW part of a band just to get
used to how received signal appear on the waterfall. After you
have done that, and know what received signal generally look
like, it is time to look for an actual Chip 64 signal. In the
USA, 7090 USB appears to be the most active frequency,
14110 and 14077 have also been reported. Check the Chip 64
for more frequency information specific to your
region. On 7090 there is also Olivia activity, Olivia
has a chirpy sounding tone, a kind of combination of MFSK16 and SSTV
sounding signals. Chip 64 is nothing like this , it is more
a "whooshing" or "roaring" white noise type of signal, not as low in
tone as MT63. If you REALLY want to hear what it sounds like
just put your Chip 64 software in transmit mode (see below)
without the radio on , and you will hear it via your computer speakers
or headphones. If you hear a Chip 64 on your radio, the Chip 64
waterfall will graphically display the signal, in a whitish colour ,
about 300 to 400 Hz wide (on the waterfall scale). To decode the
signal, simply place your mouse in the middle of the received
signal and with a few short seconds the received decoded text should
start scrolling on your screen. What is the SECOND waterfall
below the first one? Don't worry about that, more
later. If you successfully receive text, that's pretty much
it. If you have strong signal and cannot decode, make sure
the AFC box is checked and that you are in Chip 64 not Chip 128.
My received text is mostly gibberish although I see a few normal words?
Weak Chip 64 text is similar to many other digital modes, when
they fall below a threshold... errors are produced. Sometimes
random characters are displayed . You may want to adjust the
squelch setting (WRENCH icon, GENERAL, DECODER OPTIONS) to
a higher CONFIDENCE LEVEL.... 50% seems to work well. Turn OFF
the squelch via unchecking the SQUELCH box in the CONFIDENCE
LEVEL pane , lower right at the bottom of the Chip 64
screen, if you want to pull out a very weak signal.
What is this Unclocked/Clocked Thing? According to
the author, Nino IZ8BLY, "
'clocked decoding' the signal is decoded in the traditional way, that
is, without taking advantage of spread spectrum. In this case a clock
reference is extracted from the incoming signal and the decoder tries
to maintain synchrony with the symbols. Additionally, the shape of the
detected symbol (See the "chip shape" pane , lower right of your
screen) ) is displayed in a dedicated box. There might be some
conditions where clocked decoding performs better than unclocked one,
just experiment with the two."
Is the difference between Chip 64 and Chip 128?
Nino Iz8BLY states "Chip128, it is the slower but more reliable version
of Chip64, obtained by doubling the spreading code length. Nonetheless,
the baudrate and bandwidth is the same as in Chip64". I (K3UK)
have had several QSO in Chip 128 and can confirm that it appears to
improve decoding under QSB-type conditions. As yet, I have
nottrained my ear to tell the difference in sound, if there is
any, between the two Chip modes.
Appears to be TWO Waterfalls. Just What Does the Lower One Do ?
The lower one is called The
Nini IZ8BLY describes it thus
program features a special display called correloscope. It shows the presence of the code by displaying its time-offset. The
correloscope plots in a graphical way the output of the correlator. On
horizontal axis, the time frame of a code- length is represented (1/300
sec). At each sampling step, one dot is drawn: the more the
correlation confidence, the whiter the dot plotted. By plotting the correloscope in a waterfall fashion,
the user is able to perceive how the offset of the received codes moves over time. A distur bed signal
will plot an unsteady vertical trace (where the shape of this trace depends on the propagation conditions
). A weak signal will plot a steady but faint vertical trace. The correloscope can also show possible
clock drifts between the transmitter and the receiver, which are seen as slanted traces. The output of the correlator also controls
the squelch of the receiver which is turned off when the confidence falls below a certain threshold. The software has also the option to turn
off the correlator and demodulate the signal as a traditional BPSK
transmission (referred in the program as "clocked decoding"). Its
purpose is to show the differences between the two decoding
systems under different conditions. By averaging chips phase errors, a very
smooth frequency tuning is possible. This is indeed another advantage of Spread Spectrum. The averaged
phase errors, constitute a stable frequency error correction signal that can be put in feedback to the
main NCO allowing an automatic and precise frequency tuning. The correlator
In the decoding process, each receiving sequence has to be matched with
the WHP codes from the
alphabet, that is, the despreading process has to be repeated for every
WHP code. This is necessary
because in this system we haven’t just a single code as in plain DSSS,
but multiple codes present serially
and randomly at the receiver.
Thus, each chip from the arriving sequence is compared with the
corresponding chip of the reference
WHP code in the table. If the chip sign matches, confidence is
augmented; otherwise if the sign doesn’t
match, confidence is decreased. At the end of the chips, the resulting
confidence for that code is
obtained and the matching work is repeated for all the other WHP codes
in the table. The time-offset of the arriving code
sequence is calculated as the point with best confidence over a code
duration, and the corresponding code is used for decoding into text.
For better performances, soft
chips are processed. A
soft chip is a chip that does not represents discrete
states (+1 or -1) but represents the likelihood of the chip of being
"+1". This likelihood system provides
a better accuracy giving a continuous range in the confidence values,
rather than discrete steps of 1/64.
The soft bit information is derived directly from the phase error
output of the BPSK detector. Soft bit
values range linearly from 0.0 (0° angle) to 1.0 (180° angle).
To avoid in between chip synchronization, the despreading work has to
be done in time steps smaller
than one chip , thus picking with greater precision the offset point of
the code. This is done by working
with an oversampled signal respect to the chiprate. Depending on the
CPU speed, three oversampling
figures are provided: 21x, 7x and 3x; these apparently odd figures, are
all divisors of 44100 Hz, the
samplerate used by the soundcard. An higher oversample gives to the
correlator a better resolution, but
has an heavier load on the CPU. The CPU load is an actual limitation,
as it can be too high to let the
program run on some old PC workstations. The load is proportional to
the number of elementary chip
matching operations that can be executed in the time unit. Since these
elementary operations translate
into simple ADD and SUB register machine code instructions, they can be
executed in just one CPUclock
cycle, therefore the total CPU load (lower bound) can be approximately
chiplength oversample chiprate nop ´
´ ´ =
Chip64: nop = 300 × 21× 64 × 128 = 51,609,600 ˜ 50 Mips
Chip128: nop = 300 × 21 × 128 × 256 = 206,438,400 ˜ 200
current CPU clocks in the range of few GHz, it’s necessary that the
correlator has the maximum possible performance. For this reason,
integer math was used as it guarantees faster execution speeds
Chip 64 /Chip 128
Receive is OK, how do I transmit? First,
like any digital soundcard mode.. you need to make sure your signal is
"clean", free from ground loops and other nasty causes of "hum" .
You also need to set your output level to one that will not overdrive
the produced signal. I would suggest starting off with a low
power signal , nothing more than 30 watts . Getting a clean
signal is usually not a problem if you have an interface like
Microkeyer , Rigblaster, or similar commercially made products.
Home brewed interfaces can be made for less than US$15.00. A good clean
signal also requires the right combination of volume output from your
computer and gain setting on your rig. Other digital modes
usually advise one to turn up the gain to just about the point that
your meter starts to show the slightest ALC , then back off a little
more. Chip 64 has a convenient OUTPUT POWER slide adjuster, just
to the right of your macros section. Sliding the lever will
increase your soundcards output to the radio, as you increase or
decrease the output you will see the gain on your radio output meters
change, assuming your rig is in transmit..
than floating point math. In particular, the correlation routine was written in pure assembler doing
all operations in CPU registers and interlacing the machine
language instructions to take advantage of the
processor’s execution pipeline.
already, I know all that stuff...I just want to get on the air.
To answer a CQ call or respond to a CQ call , you need to
get the software to key your rig. Chip 64 automatically goes in
to transmit mode if you place your cursor to the transmit text window,
located just above the waterfall. After you place the cursor
there, pressing any key on your keyboard will start the transmit.
You can either manually type your transmitted text or use some of your
pre-programmed macros. Most people use a combination of
both. When you want to end your transmission you can choose
a macro that has an $off command at the end, issue a CONTROL X from
your keyboard , or go to the top of your screen and select
TRANSMIT then end transmission.. It is generally best to
transmit with the waterfall frequency ( lower right hand corner
of your screen) around the 1300 to 1700 range , outside of this range
and weird things happen when you transmit. I'll leave that to
someone else to explain. Chip 64 will conveniently center itself
on 1500 Hz if you simply RIGHT CLICK on the waterfall. IF you
want to change the RIGHT CLICK results to a frequency other than 1500
Hz, go to WRENCH ICON, WATERFALL, and then
change the frequency in the WATERFALL DISPLAY RANGE /RICK CLICK
FREQUENCY box. You can also change some of the default
ranges for your waterfall in this area.
Can I TYPE
AHEAD? Yes you can. To do this you must start
your to-be-transmitted text with an asterisk ( * ). Anything you
type after the asterisk will not be transmitted UNTIL you send a
CONTROL T from your keyboard.
Macros don't seem to send the other person's info !
Macros like $OTHER , $OTHERNAME , $OTHERQTH and so on
...require you to tell the software this information. Click on
the LOG icon , upper right of your screen, and a simple log entry
screen will appear. If you enter in the other station's callsign,
name, QTH and RST, you will be able to reference this information in
OTHER FAQ :
I have downloaded and
installed Chip64. I am using Windows XP on a HP Pentium 3 Gig
machine. Any mouse activity onthe waterfall window causes the the
to freeze. How do I correct
Well fellows, I have answerd this question now a few times
already on several refelctors. Here again. If you use a Intel CPU with
Hyperthreading and this is enabled in the Bios Setup, disable
Hyperthread and all is ok- via
That's it, until a better help file
comes along. Feel free to email any additional items or
suggestions for revisions.
73 de Andy K3UK