Sura 1The first of the IRFU SEE campaigns in Russia, Sura 1, was to take place in September 1990 (from the 17th to the 27th). Heating frequencies used were 4785 kHz, 5828 kHz, 7814 kHz, 9050 kHz, 9310 kHz, 5425 kHz and a somewhat continuous scale of frequencies around those. The Russian conditions provided possibilities not yet encountered, such as practically unlimited frequency stepping.From IRFU a dense scientific team went on this campaign to Russia, there was Eugen Veszelei, Bo Thidé, Thomas Leyser, Mattias Waldenvik and Simon Goodman. From the Naval Research Laboratory of Washington DC there was Paul Bernhardt undertaking optical measurements. The spectrum analyser HP3585A, and, of course, the home built John Silver, which had been upgraded with an FADC unit and further tailored for its purpose by Eugen Veszelei, as well as a HP8644A, which served as a signal generator went along the IRFU team to Russia . The different scientist focused on different aspects of HF pumping. Gyro harmonics were generally thoroughly investigated. SEE, at HF pump frequencies of four times, and five times the electron cyclotron frequency, was systematically experimented upon. Mattias Waldenvik examined the temporal properties of the "Downshifted Maximum" thoroughly, its growth, overshoot, and anti-correlation to the pump, and time evolutions for different part of the "Downshifted Maximum". The results were presented in Mattias Waldenvik's PhD dissertation. For the first time a second "Downshifted Maximum" could be detected as the pump frequency increased from a cyclotron harmonic. Mattias and Simon could also conclude that the "Broad Upshifted Maximum" grew faster than its sidebands, which was consistent with the peak being at a resonance. Double frequency experiments, short heating periods over layered with long heating periods with two frequencies, so called Frolov experiments were conducted to examine the peak at the arithmetic mean (AMPs) of the two frequencies and time histories of this peak was taken. John Silver audio recordings were stored digitally on videotapes, and both John Silver and HP3585A spectra are stored in the IRFU data base, while the HP3585A spectra are present as backup in hardcopy as well.
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