Ionospheric sounding - The G3PLX Chirp Project

Passive Ionospheric Sounding and Ranging

Chirp Statistics

It is not possible to distribute a definitive list of all known chirp sounders on a web site, since many of them change from day to day, or week to week. The list below gives those that are known to be reasonably stable, or rather were at the time of publication! Current observations are generally distributed by email.

The times quoted here are the source chirp time, i.e. the time that would be measured by a receiver on the transmitter site. You can estimate your chirptime by adding 1 ms for every 300 km of range from the source. For example, for a chirp time of 300:245.000 and a range of 10,000 km, expect the signal to arrive at about 300:245.030.

Chirp times are typically quoted in the form period:chirp time, where the period is in seconds, and the chirp time is the zero frequency extrapolated time of the first chirp transmitted each hour.

Period:Chirp Lat Long  Approx location
-------------+--------+--------------------
900:178.5496  33S 149E Canberra, Australia
300:250.0000  35N 34E  Cyprus
300:224.14595 52S 59W  Stanley, Falkland Is
300:77.94247  54N 03W  Inskip UK

A summary of known chirps is available via email on a regular basis to those involved in the project. A recent copy of this summary in electronic form suitable for spreadsheet use is available here. The summary can also be viewed online in html form.

mail