1. Telecom TRAINNING: Radio
15 mai 2018

2. Telecom type sum-up (early 2016)
70 bases in total:
31% Vsat => 22 bases in 9 countries (32% in 2013…)
36% DSL or Fiber optic => 25 bases including 11 capitales (33% in 2013… 14 capitales)
27% Radio internet(Wifi/Wimax/WLL) => 16 bases including 9 capitales (20% in 2013…Radio becomes better than DSL…)
50% Radio HF/VHF => 10 missions (mainly africa)
6% 3G keys => 3 bases (8% in 2013, but explode for backup use…)
0% still with BGAN => 0 bases… (7% in 2013)

3. Electromagnetic wave Photon Caracteristics of a wave: Amplitude
Frequency (Hz)
Lenght (m)
Speed (light
speed)
:                                                                                                           
15 mai 2018

4. Radio Frequencies 15 mai 2018 18 MHz Band: 18068 - 18100 CW CW
Digimode, CW
IBP
Phone, CW
15 mai 2018

5. Waves transmission trough antennas
The perfect antenna has the same physical length than the frequency we want to use (reception or transmission).
In this case almost all the power of the transceiver is tranmited into electromagnetic wave.
Electromagnetic wave
Transmission
Reflected power
If the antenna is not well choose of if there is to many obstacles, the power of the transmission is dangerously reflected into the transceiver.
Electromagnetic wave
Electromagnetic wave
Tranmission
Reflected power
15 mai 2018

6. Radio material Managing the relfected power DANGEROUS !
The only feed back you have : SWR meter
GOOD
PERFECT
15 mai 2018

7. Storm Lightning protection
So we need to protect the radio antennas
Lightnings can go up to volts
And radio antennas are a important target.
15 mai 2018

8. To optimize the Radio transmission
Technicaly speaking :
NEVER TOUCH THE radio ANTENNA WHILE TRANSMITING !
Position your radio antennas as hight as possible (6 meters) except for NVIS, far from any obstacle.
Take great care of the connections (grease and silicone).
Take great care of the cables (respect lenght, do not bend).
Respect the earth connection.
May 15, 2018

9. HF radios
15 mai 2018

10. Connecting HF Radios (ACF Doc…)
:                                                                                                           
Do not forget the earth connection (half the antenna ! Double the performance... (see annexe)
15 mai 2018

11. Connecting HF Radios (ACF Doc…)
:                                                                                                           
Do not forget the earth connection (half the antenna ! Double the performance... (see annexe)
15 mai 2018

12. To optimize the HF transmission
Antenna position
Topview
Sideview
15 mai 2018

13. VHF radios
15 mai 2018

14. VHF material GP340 GM340 Antenna: 16 channels 136 – 174 MHz
5 watts (Tx)
8 to 14 hours autonomy
Computer programming
265 euros
GM340
6 channels
136 – 174 MHz
25 Watts (Tx)
Computer programming
About 300 euros
Antenna:
As high as possible
15 mai 2018

15. VHF repeater
In duplex mode : one frequency to transmit, another one to receive.
Duplex
TX: KHz
RX: Khz
VHF contact is similar to visual contact
VHF reapeater can overcome the obstacles.
Duplex
TX: Khz RX: KHz
Duplex
TX: Khz RX: KHz
In simplex mode : the same frequency to tranmit and to receive.
Simplex
TX-RX: KHz
Simplex
TX-RX: KHz
15 mai 2018

16. - + ++ +++ VHF RADIOTESTS
If the coverage is not sufficient (< green zone for ex),
=> IMPROVE THE COVERAGE
Material
Power
Altitude
Range
VHF Handset
VHF Mobile
VHF Base
VHF Repeater
5 watts
25 Watts
25 Watts
25 Watts
About 2 meters
About 3 meters
About 6 meters
About 20 meters - + ++
+++
15 mai 2018