الفهرس 
INTRODUCTION.Only 14 pages are availabe for public view
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Abstract
This thesis presents an extensive theoretical and
experimental study of radio noise resultine at the
vicinity of the 500 kilo volt Egyptian over head transmission
lines in different climatic conditions. It is
believed that this is the first time that such an
extensive field study has been carried out on Radio
Noise (RN) at desert climates. The results are compared
with those obtained at some other countries of different
climates. It also presents a derived formula for
calculating the radio noise at the vicinity of the 500
kV over head transmission lines. The set used for the
field measurements consists of a sensitive reciever
which can be adjusted to any frequency between 9 KHz to
30 MHz, connected with either rod or loop antenna
through standard cables;The set measures both the radio
noise and the induced voltage, generated by the high
vol tage t r-anamdssdon lines.
The site of measurements Tias at the Cairo/Alexandria
desert road at the 22 Kilometer from Cairo where the 500
kV over head transmission lines crosse the road, and
along the transmission lines for about half kilometer in
the desert between towers number 506 and 507.Frequency of the set was adjusted at 1 MHz as
specified in the CISPR and also some measurements we re
taken at a 0.5 MHz frequency adjustment for comparison.
The lateral profile of the radio noise which is the
variation of radio noise with distance, was determined.
Measurements were taken at different weather
conditions during a period of more than one year, where
the temperature varied from 20°C to 55°C and the humidity
varied from 20% to 90%, as to study the effect of weather
conditionson radio noise resulting under the 500 kV power
into two categories, fair weather where the ambient
transmission lines. The weather conditionsare classified
temperature varies from 20°C to JOoC and the humidity
varies from 20% to 50% and foul weather where the ambient
temperature may reach up to 55°C or more and the humidity
is up to 90%.
Other family of measurements were taken under
experimental lines at the Egyptian Pyramids Extra High
Voltage Research Center to check the effect of voltage
variation on the measurine values of radio noise.
Measurements were ’t abuLat ed and plotted into curves
and compared with those taken in some different parts of
the world. These measurements and curves had. lead to the prediction of
a mathematical
:orUlL;.lafor
calculating
the radio
noise resultip-e at
the vicinity of
the 500 kV
over head transmission lines
in both weather
categories.
The study concluded
the following:
1. The radio noise generated
at
the vicinity
of the
electric power lines were affected by the climatic
condi t Lon a,
2. High ambient temperature leads to an increase in the
radio noise level.
3. Increasing the humidity leads to a decrease in the
radio noise level.
4. Increasing the voltage level of the power line leads
to an increase of radio noise level, for voltages
above 150 kV.
5. There was a background radio noise level of about 40
dB above 1 micro volt/meter generated from environmental
sources other than transmission lines.
6. The foul weather radio noise level was greater than the
fair weather radio noise level by an amount of about
10 dB)- Vim.
;
7. Comparison between radio noise measuremenwunder the
Egyptian 500 kV transmission lines vii th those under
similar lines in North AmericR showed that the
Egyptian foul weather values are less than the North American foul weather values. and the Egyptian fair
weather velues are higher than the North American
fair weather values.
A mathematical computation formula was predicted to
calculate the radio noise level at the vicinity of
the Egyptian 500 kV transmission lines at any
lateral distance and in both weather categories.