If you have a Psk Meter connected to
a serial port and powered up you
should see the Comm: selector showing the proper port number. If
for some reason the Psk Meter was not found you can force a selection
from the pull down selection box (but if the program did not find the
meter it probably isn't connected or powered on). The program
will also query
your computer for all sound cards that are are installed. I use
two sound cards; one for digital communications and the other for
system sound / music, etc. This keeps my computer from
inadvertently sending a windows alarm or other sound to your
transceiver. No one wants to hear "you have mail" on 20 meters or
any other band. If you only have one sound card I suggest that
you disable all system and other program sounds while on any digital
mode that uses the sound card.
Well, you will have to select the proper sound card as the program has
no way of knowing which one you may be using. Do that now.
R1 - this is the resistor
value on your Psk Meter for high power (39 k) or the QRP (6.8 k) that
is jumper selected.
and displays all
power values as RMS for a transmitted IDLE signal.
This allows you to more easily adjust your output power to match
averaging SWR / Power Meter. If you built your Psk Meter with the
supplied resistor values you do not need to change this. You may
have opted for a much lower or higher power range and changed the
resistors. If so, then enter the actual values used.
Red - Inter Modulation Distortion (IMD) figure of merit above which the
signal and spectrum display turn RED ... this is not desirable.
You will be seen, heard and disliked by all of the other psk operators
on the band.
Yellow - IMD figure of merit above which the signal and spectrum
display turn YELLOW ... try not to operate in the yellow. You
might be ok under really noisy conditions, but when the band is open
and QRN is low your received signals will show the additional sidebands.
When the IMD is below the Yellow
threshold your signal displays in GREEN ... nice ... try to keep it
there. You will be proud of your transmitted signal, it will be
easier to decode, and give a higher percentage of printable
characters. Most important, you will not be interfering with
other psk operators on the band.
TgtP - The target output power (at idle) when automatic
level conrrol is selected. (recommend 15 QRO)
The Psk Meter asynchronously samples the transmitted waveform. It
takes 64 8-bit samples spaced over the full cycle of the idle waveform
when transmitting Psk31. The data set must be rotated about
itself to achieve what looks like a synchronous sample set.
During idle this nearly always produces a perfect sample set.
When characters are being transmitted the data set may or may not be
useful for subsequent analysis. Data set culling is used to
insure that only valid sequences are used for analysis. A valid
sequence will have a complete first 1/2 cycle of the waveform available
for analysis. All samples are shown including those that do not
qualify as valid for analysis.
Min - number of a/d bits required to declare the data set valid.
Increase this value if you have a large interfering signals on the
antenna such as during field day. A value of 4 insures that the
transmitter really is on, but does not degrade any subsequent
analysis. Leave this number alone unless you can see the
interference on the display
Filter - Coefficient for a simple first order difference equation used
to filter the raw data values:
Vn = (alpha)*Vn-1
change this to 0 if you do not want any filtering. I find
that 0.8 gives satisfactory results with my Delta II.
Pressing the SAVE button will create a "pskscope.ini" file in the same
directory as the executable file. This file will be read on
subsequent program executions. If you want to start from scratch
just delete this file. The ini file contents are as:
You could alter this file with notepad or some other editor but I do
not recommend doing so. You will get unexpected and probably
undesirable program execution.