About this episode
The episode explores the standardization of S-units in amateur radio and the discrepancies in signal strength measurements across different radios.
Foundations of Amateur Radio The other day fellow amateur Randall VK6WR raised an interesting question. Using his HP 8920A RF Communications Test Set, which you might recall from our adventures in measuring radio harmonic power in 2023, that report is on my Github repository, but I digress, Randall wondered if the signal strength he was seeing on several radios were the same and discovered that in fact they were not. It made Randall ask who set the standard and following on from that, what does this look like in the real world? In 2014, episode 149 of the series "What use is an f-call?", I published an article titled "The simple S-unit". In it I referred to a standard for S-units defined in 1981. Unfortunately, I didn't provide any references, so, armed with more than a decade extra experience, Randall encouraged me to investigate. Twenty seconds into my search, I discovered IARU Region 1 Technical Recommendation R.1, which has four statements related to the topic at hand. Under the title "STANDARDISATION OF S-METER READINGS" it states that: 1. One S-unit corresponds to a signal level difference of 6 dB, 2. On the bands below 30 MHz a meter deviation of S-9 corresponds to an…
Topics covered
- S-units
- signal strength
- standardization
- IARU recommendations
Keywords
- amateur radio
- signal level
- dB
- RF Communications Test Set
Mentioned in this episode
Products: HP 8920A RF Communications Test Set, IARU Region 1 Technical Recommendation R.1, Morse Code, the HF Managers Handbook
Books & works: What use is, The simple S-unit, STANDARDISATION OF S-METER READINGS
Places: Netherlands
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