The first real post for 2020 is actually this posting which serves to finish something I had started in October 2019 in preserving the sounds of HF weather broadcasts. While I had successfully catalogued a good number of transmissions from different countries using KiwiSDR receivers around the world, I was still far from receiving all of the transmissions on the HFUnderground page. Unsatisfied with the results, I decided to take a more systematic approach with the elusive stations.

Monitoring++

While the last monitoring effort was perhaps broadly successful on many of the stations, a number of them remained elusive for a number of reasons. One of them is their transmitting location and power which may limit their reach. Where KiwiSDR receivers are sparsely located, the opportunity for reception can be limited. This is made even less probable where strict time limits are enforced on reception.

Instead of making monitoring convenient for myself by scheduling recordings prior to going to sleep (which invariably is usually day-time at the receiving site and results in time-outs occurring prior to local night time), I decided to get myself up early some mornings to schedule recordings just as the receiver is entering local night time. I also opted to use a wider number of receivers, including those with time limits, as a last-ditch effort to try and catch the signal. I tried all listed frequencies for the elusive stations, monitoring for as long as it would allow me to do so, up to 24 hours for each listed frequency at more than one site. For stations with very few transmission schedules, I even took the time to try and monitor the frequency in person, often to negative results. I know that we are in a relatively quiet solar cycle which doesn’t help – but these stations might not be around by the next one! Unfortunately, I often still came up short, but at least I was able to receive a few more stations.

The downside is that now my VPS static IP has been banned by a few good KiwiSDR receiver sites as a result of the long-term unattended scripted reception being parked long enough for the owner to notice. If anyone was inconvenienced by this, I am truly sorry, it was not my intention. I was just (perhaps) too focused on trying to catch stations without having to sit and listen for them manually!

Results

Below are the results of the monitoring effort, grouped by country. As with the last posting, you can click on the link or spectrogram image to hear the audio file. As this was basically a mission to catch the transmissions not heard the first time, many of the signals presented here are weak or difficult to read as compared to the first part.

Argentina

A transmission from Argentina was received at 20191211T1748Z_4149kHz, albeit weakly. It seems to be announced by a live person, in Spanish.

Bulgaria

A clear transmission was received from Bulgaria’s Varna Radio at 20191216T0704Z_3740kHz. Announced by a live voice with a noticeable amount of hiss in the background, it is read in English by both male and female announcers. A team effort!

Canary Islands

The first transmission is prefixed with a securite call by a male voice announcing navigational warnings broadcast. This is followed by the voice synthesis system which takes turns alternating between English and Spanish – received 20191210T0634Z_1689kHz. The second transmission is prefixed by a woman announcing the weather broadcast in both English and Spanish. This is followed by the voice synthesis system in both English and Spanish. Received 20191210T1605Z_1689kHz. Both transmissions clearly identify themselves as from Las Palmas Radio.

While monitoring the transmissions, four PAN PAN calls were recorded which were voiced by different operators at different cadences. Three were of the same message, while another was a relayed message from Germany. Tran