Saturday, April 13, 2024

Interference during the recent Namibia to Europe TEP tests - Apr 2024


There have been many remarkable Trans-Equatorial Propagation (TEP) openings recently on the 144 MHz band from Namibia to Europe. This all started off when a group was established on WhatsApp where individuals in Europe and Africa exchanged messages to try and co-ordinate the tests.

The problem with evening type TEP is that the signals are often very distorted at 144 MHz and modes like FT8 often don't work. To address this issue, the group decided to try the Q65 mode which has been a huge success. They picked the frequency of 144.190 MHz to carry out these TEP tests.

The choice of frequency is important because it was just a frequency chosen to carry out TEP tests, it's NOT the official Q65 frequency.

The problem now is that as news of the TEP contacts has spread, European stations are starting to work each other on 144.190 MHz with Q65. The problem here is that they are blocking the weak TEP signals from Africa.

The organisers of the TEP tests moved the frequency to 144.192 MHz to avoid the interference from EU to EU contacts but the central message is that the area around 144.190 MHz should be left clear for only TEP contacts from Europe to Africa.

In terms of sequence, Africa always transmits first, Europe always second.

No comments: