The 5 MHz Newsletter No 12
You can down this informative newsletter by Paul Gaskell here
May edition of the 5MHz Newsletter by Paul
ACCESS TO 5MHz
SARL Members will have access to 5 250 and 5 290 kHz on registration requiring the completion of a registration form which can be downloaded here.
Once completed please email it to firstname.lastname@example.org. Processing time is a max three days.
All registered users are listed here
Look at the latest WSPR activity from ZS1
Stewart ZS6SGM's presentation at the Cape Town RTA certainly awakened interest in WSPR and the SARL Propagation research project
5MHZ PROPAGATION RESEARCH PROJECT SHOW UNEXPECTED RESULTS
5MHZ ACTIVITY WEEKEND
Change in frequency
Please note that the SARL allocation in the 5MHz band has been changed. 5250 kHz has changed to 5290 kHz.
Most WSPR stations have already changed. Please make sure you do not operate on 5250 kHz. No change to the 5260 kHz frequency
Latest version V1.03 can now be down loaded here
If you are interested in the mysteries of propagation then WSPR is the tool at your disposal. To experience this fascinating tool, all you need is an SSB transceiver, simple antenna, a sound card interface to connect the transceiver to your computer and internet access.
WSPR is short for Weak Signal Propagation Reporter and is pronounced “Whisper”.
It is important to note right away that WSPR is not a QSO mode. It is used to broadcast a position, call sign and power level and see who hears and decodes it. The receiving station can work out how far the signal travelled and how strong it is on the receiving end.
The mode that WSPR uses is called MEPT-JT. MEPT means Manned Experimental Propagation Transmitter. The JT part is Joe Taylor's initials. Joe Taylor K1JT also developed the mode WSJT which is used for “moon-bounce” communication. In 1993 Joe Taylor shared a Nobel Prize in Physics with Russell Hulse, for some work they did in their field of Astrophysics. He obtained his license as an Amateur Radio operator as a teenager and as a result became interested in radio-astronomy.
This tutorial covers the reception and decoding of WSPR only. TX will be covered in later tutorial. Download it here
Propagation research on 5 MHz some interesting results
Propagation Research undertaken by radio amateurs on 5 MHz shows some early and interesting results using the Weak Signal Propagation Reporter software (WSPR) . Read the article on the EngineerIT website. Put your browser here:
STUDIES OF IONOGRAMS SHOW SUPREMACY OF THE 5 MHZ BAND
The ionograms generated by the South African ionosonde network clearly illustrate the supremacy of the 5 MHz band for short range, near vertical incidence skywave (NVIS) communications under certain conditions. These typically happens during the morning and late afternoon when the 7 MHz band does not support short range, sky wave communications and the 3.5 and 1.8 MHz bands suffer from high noise levels.
During the middle of the day the 7 MHz (and 10 MHz during high solar activity) band is typically the most effective medium for short range, sky wave communications.
Permanent access to the 5 MHz band will ensure that the amateur radio community can efficiently contribute to emergencies requiring short distance communications beyond line-of-sight as typically required in hilly and mountainous terrain.
The South African ionosonde network is unique in Africa and place South African radio amateurs in the very fortunate position to monitor reigning, short range propagation conditions and to improve their skills and experience accordingly.
An article by Hannes Coetzee illustrated with ionograms is available for download here