1. Differences between Digisondes, Dynasondes and Classical Ionosondes in the projects: DIAS and LOIS. Christer juren IRF Kiruna

2. A discussion about different philosophies regarding Ionosondes suitable to be used in the project DIAS (http://www.iono.noa.gr/DIAS/) and LOIS.DIAShttp://www.iono.noa.gr/DIAS/ The history of The Swedish Ionosondes (up to Transpusondes) are described with illustrations from very old soundings and newer ones. Object oriented view of the Ionosphere. The digisonde is closely compared with the dynasonde; two quite different types of concepts! What type of sounding is interesting for DIAS / LOIS?

6. Transpusonde Computer part Dark red: 286 PC Green: RS232 connection Blue: Transputer T800 White: Transputer T200 Light red: Xilinx 3030 Yello: GPS Gray: samplingunit (T200)

10. 4 * myIonosonde

11. Bill Wright; Dynasonde Bodo Reinisch;Digisonde

12. The Dynasonde collects echoes in form of detected discrete pulses described by: time, amplitude and some phases. The Digisonde collects time series for frequency and polarization. !Both defined by the transmitter!

13. The Dynasonde transmits plane polarized waves in form of 100 micrSec shaped pulses. The pulse power is about 1- 10 KW. The original receiving antennas were from four to six in number and each of them consisted of broadband active dipoles about 5 meters in length. Dynasonde Receiver dipole in Lycksele

14. Dynasonde The dynasonde transmiting antenna will always transmit plane polarized waves. The constructions vary; traveling wave dipole, delta, logperiodic, broad band dipole (Lycksele).... Inverted logperiodic at Tromsö; the feedpoint:

15. An ionogram sampled with a soundcard. The red curve is a part of an original time series for one frequency. The ionogram is a little bit hacked, which is due to the type of sounding,. ”Frequency” along the horizontal! Dynasonde

16. The antenna layout and the definition of the data for one detected pulse, which is the complex amplitudes for the maximum in the timeseries around the accepted pulse. dynasonde

18. One Digisonde receiving antenna at RAL UK A digisonde has four receiving antennas. Each consists of two crossed dipoles. The signals will be combined so the output will represent the O- and XO-modes separately. Digisonde

19. Digisonde transmiting antenna in Juliusruh. Two crossed delta antennas. They generate right or left circular polarized waves. Digisonde

23. The Transpusonde at Uppsala transmits pulses and a Lois receiver receives them.

24. Conclusion Go the Dynasonde way together with LOIS receivers. Use the concepts of the Dynasonde.