SUDDEN IONOSPHERIC OF DISTURBANCES - SID Month: JULY YEAR: 2021 Observing Station: OBSERVATORY U P I C E CZECH REPUBLIC Transmitter coordinates: Receiver coordinates: Lat.: 63 51 1.31 N Lat.: 50 30 26.6 N Long.: 22 28 0.38 W Long.: 16 00 43.5 E Sea level: 416 m Frequency: 37.5 kHz Band pass: 308 Hz a 80 dB Chart speed: 3.4 cm/H Recorder time constant: 1 min Date Start End Max. Imp. Def. Dur. Type REMARKS UT UT UT SID min. 20 0836 0940 0857 1 2 54 5 P UNCERTN NO OBSERVATION 1.7. - 12.7. 0000 2400 15. 0750 1300 22. 0950 1140 29. 0800 1400 P positive efect Evaluated by J.Klimes