About a week ago, Joe Taylor posted a message about the FT2 “developments”. Citation: Compared with FT4, “FT2” is significantly less sensitive, needs twice the bandwidth, and has far more decoding failures caused by timing errors. The mode is hardly usable without full (or nearly full) automation. We have no plan to add a twice-speeded-up… Continue reading »
Having read the introduction of Decodium, as being “the fastest” mode, my first take was “too good to be true”. Physical laws cannot be broken. So let’s have another look at things. Popularity PSKreporter has a statistics page, which shows the number of spots received. A snapshot taken on March 10, 2026 shows that the… Continue reading »
A quote from the website (ft2.it): “Complete QSO in 7-11 seconds. Theoretical rate of ~240 QSO/hour, ideal for contests and DXpeditions.” OK, game on. Let’s check. What about FT8 Superfox? The user manual states: (…) Standard messages include up to 9 Hound callsigns: as many as four may receive numerical signal reports to start a… Continue reading »
Today, the 1st of January 2026, it is exactly 50 years ago when my initial VHF licence became valid. Because one had to return documents to the administration when the licence was changed, which happened in 1977 after the CW test was passed. Details were typed on a printed document. Before 1976, only PA0 prefixes… Continue reading »
A bit like the fashion for middle aged men, my good old Hewlett Packard 8568B got new clothes. In my opinion, it is one of the masterpieces of Hewlett Packard spectrum analyser design. Even today, the specifications are hard to beat with new equipment in the “amateur price” range. I will return to that. The… Continue reading »
For some time, I suffer from tremendous interference from various sources. The worst one is LED lighting which generates very strong interference in the 50 MHz band. I wanted to see what the interference would be like we still had analogue television. We used to have CCIR system B on VHF and the channel 2… Continue reading »
A priori is a Latin phrase which – in the context of FT8 etc. – translates to prior knowledge. This article aims to explain what a priori decoding does. It also discusses how AP relates to a “valid QSO”. A little paragraph is dedicated to to information theory. The article also illustrates that AP is… Continue reading »
Recently, I read about noise reduction with artificial intelligence. AI is quite fashionable and, in my view, is seen too much as a panacea. Here are some thoughts based on some theory. 1. Noise If there is “pure noise” (white noise) then you cannot filter out that noise. AI or no AI, it is impossible…. Continue reading »
What the… are hash collisions? What has it to do with FT8? This article explains that the FT8 protocol can confuse call signs and the software seems to behave erratically. What is a hash? In short, a hash code is a number, usually calculated via bit operations. Hash codes are widely used in data storage… Continue reading »
Over time, items were added to the inventory of measurement instruments. But it all started with some simple things, because professional instruments were way out of reach at the time I was licensed in 1976. We had to cope with uncomplicated equipment to be able to “guesstimate” what we were doing. The grid dipper One… Continue reading »