http://nopr.niscpr.res.in/handle/123456789/37373 2026-10-09T22:14:56Z 2026-10-09T22:14:56Z Rao, B Ramachandra Rao, M Srirama Ratnam, S Raja Rao, D A V Krishna Rao, E Bhagiratha http://nopr.niscpr.res.in/handle/123456789/37566 2016-11-25T05:11:49Z 1976-03-01T00:00:00Z

Title: Study of Meteors during Quadrantid Shower Period by Forward Scatter of vhf Radio Signals between Debra Dun & Waltair Authors: Rao, B Ramachandra; Rao, M Srirama; Ratnam, S Raja; Rao, D A V Krishna; Rao, E Bhagiratha Abstract: Results of the study of meteors recorded by vhf forward scatter propagation between Dehra Dun and Waltair during the Quadrantid shower period are presented. High meteoric activity is recorded on 3 Jan. when the Quadrantid shower is known to exhibit peak activity. The diurnal variations in the activity of shower and non-shower meteors on 3 Jan. are studied. The variation of daily mean hourly rates of radio meteors during this period is found to agree well with that of visual meteors over Waltair. Page(s): 103-104

1976-03-01T00:00:00Z Chiplonkar, W Puranik, G G http://nopr.niscpr.res.in/handle/123456789/37564 2016-11-25T05:09:45Z 1976-03-01T00:00:00Z

Title: Further Analysis of the vlf Atmospherics Data at Poona Authors: Chiplonkar, W; Puranik, G G Abstract: Using the method of correlation coefficients the atmospherics data recorded at Poona simultaneously on 27, 10 and 1 kHz bands during the period June 1968 to October 1969, have been analyzed to study (i) the relationship between the hourly integrated intensities of these emissions and (ii) the variation of this relationship from month to month in each case. The most significant result is that almost all the monthly correlation coefficients as well as the total data period correlation coefficients are negative and significant. The total correlation coefficient values are in the following increasing order of magnitude. The period Feb.-Mar. 1969 showed a sharp transition from lower to higher monthly correlation coefficient values than the corresponding total values in all the three pairs of bands. Three regression equations between the pairs of monthly values have also been deduced which indicate, in a general way, that the 10 kHz band correlates well with both the other two bands which among themselves do not correlate in this manner. However, the present analysis is not penetrating enough to probe deeper into the nature of atmospherics Sources. Page(s): 100-103

1976-03-01T00:00:00Z Naidu, J V M Rao, B Ramachandra http://nopr.niscpr.res.in/handle/123456789/37563 2016-11-25T05:08:27Z 1976-03-01T00:00:00Z

Title: Effects of Geomagnetic Storms on LF Amplitude Authors: Naidu, J V M; Rao, B Ramachandra Abstract: Certain geomagnetic storms produced anomalous variations on the low frequency amplitude records. One such event, which occurred during 16-23 Apr. 1973, is studied. This event appeared suddenly with an increase in amplitude, associated with fast and deep fading, appearing simultaneously on the two LF singals, and vanished simultaneously on the last day of the event. The amplitudes of the LF transmissions from Madras on 292 kHz and from Bhubaneswar on 287·5 kHz were monitored at Waltair. The high phase coherence observed between the fading patterns of the two amplitude records, and the existence of dominant periods at 3·5, 5·0 and 16·6 sec obtained from power spectral analysis indicates that this phenomenon may be due to a fast moving disturbance, similar to hydromagnetic waves. Page(s): 98-99

1976-03-01T00:00:00Z Murthy, B Suryanarayana Rao, B Ramachandra http://nopr.niscpr.res.in/handle/123456789/37561 2016-11-25T05:06:28Z 1976-03-01T00:00:00Z

Title: Radio Reflections from Sea Waves Authors: Murthy, B Suryanarayana; Rao, B Ramachandra Abstract: Phase path variations of the reflected radio waves on a frequency of 2.4 MHz, around 70 km level at Waltair are found to be smooth and continuous with consistent change of phase path for extended periods of time, particularly in summer months. These are interpreted in terms of reflections coming from sea-waves. Page(s): 97

1976-03-01T00:00:00Z