Thanks Ian and Tony. I know Peter a little since he lives near my home
town, and have corresponded with him a few times over the years. Last we
heard from him on this group he expressed his intention to become a hermit
after someone distributed an alpha version of a digital voice application
that he did not one in the public domain.
Anyway, the link to Murray's page took me to Chirpview, and this
What you need to use ChirpView
Your computer
1. A PC-compatible running Windows 95/98/NT4/ME/2000 etc, though so far
ChirpView has only been tested on Windows 95 and 98.
2. Pentium (or equivalent) CPU running at 100 MHz or more - this represents
my best guess based on the software requiring about 33% available CPU power
on a 266 MHz Pentium-II. Although it might run on a 100 MHz machine, it may
be very prone to losing audio data if you try running other software at the
same time.
3. 16-bit stereo soundcard
Your HF receiver
1. USB mode with a normal speech SSB filter (i.e. 3 kHz bandwidth)
2. Ability to turn off/override the AGC and use a manual “RF gain” control.
This is not absolutely essential, but if the AGC is still operating,
ChirpView cannot correctly measure signal levels.
If you want to make precise measurements, the frequency accuracy and
stability of your receiver must be good. ChirpView receives sounders which
sweep at 100 kHz/sec, so a frequency error of just 100 Hz gives a timing
error of 1 millisecond.
In addition...
ChirpView requires an accurate timing reference. The best option is a GPS
receiver with a pulse-per-second (PPS) output. You need to connect the GPS
receiver’s NMEA data output to one of your computer’s serial ports, and the
PPS output to the RIGHT line input of your soundcard (via an appropriate
attenuator).
Alternatively, you can use a time signal such as MSF (in the U.K.). For this
you need an SSB receiver which can tune to the MSF signal and give (say) a 1
kHz audio tone from the MSF carrier. This should then be fed into the RIGHT
line input of your soundcard. Other time signals may also be suitable: they
must produce an audio tone which goes off for a short period (say 100 ms)
exactly on the start of each UTC second. If you use this option, you will
not be able to make high precision measurements using ChirpView.
Other options for timing reference may be added in later releases of
ChirpView.
I think I will give it a try, 73 Andy K3UK
On Wed, Aug 4, 2010 at 7:26 PM, Tony d...@optonline.net wrote:
Andy,
Is there any easy way to detect these signals or sweeps ? Andy K3UK
Check out ZL1BPU's page - http://www.qsl.net/zl1bpu/IONO/chirps.htm
Tony -K2MO
