Last Edited 07 October, 2019 Old items removed.
Chirpview http://www.andrewsenior.me.uk/chirpview Chirpsounder monitoring. (I use the "Public Beta" version.)
I have been playing with "Chirpview", a program that records
signals from chirpsounders. These use transmitters that smoothly move frequency
according to an accurately defined schedule. Everyone must have heard them as
they swish past a frequency, a typical one starts at 2MHz and moves up at the
rate of 100KHz per second to 20MHz or more. A receiver synchronised to the
transmitter records signals from the transmitter. They are often used to
determine the best frequency to use over a particular path, or maybe just for
research.
If, starting at the correct second, a receiver is stepped at the rate of 100KHz
per second the sounder can be followed and Chirpview" will record the
strength of pulses received, an ionogram can be plotted.
My initial thought was to use HRD's direct entry feature, "highlight"
the 100KHz digit and press the "up" arrow each second. (One of the
many frequency control features of HRD)
However, I thought of the risk of RSI or, more likely, boredom and came up with
a solution.
I opened up an old keyboard and connected the contacts of a reed relay across
the "up" key contacts, actuated the relay from the "one pulse per
second" signal from the GPS used to synchronise "Chirpview".
Ionogram
of propagation between Preston, Lancs and Cowes at 0845 on 19 March. Horizontal
axis is frequency MHz. Propagation present between 3MHz to 8MHz. Vertical is
propagation delay in mS, this is not accurate, the technique introduced an
error.