RSQ system
The RSQ system is used to assess received radio transmissions in digital operating modes (such as PSK31 ) in amateur radio . It is based on the RST system that is used in telegraphy ( Morse code ) and speech radio communications. Here, the readability ( R : readability ), the signal strength ( S : signal strength ) and the quality ( Q : quality ) of the signal are assessed with digits. In contrast to the RST- the RSQ system has only 5 instead of 9 levels for the parameters S and Q. To ensure a certain degree of comparability, these are therefore only numbered consecutively with odd digits. Mean:
R - intelligibility
| code | evaluation | |
|---|---|---|
| 1: | not readable (0% readable) | |
| 2: | single words readable (20% readable) | |
| 3: | readable with difficulty, many missing characters (40% readable) | |
| 4: | legible with practically no difficulty, occasionally missing characters (80% legible) | |
| 5: | perfectly legible (more than 95% legible) |
S - signal strength
| code | evaluation | |
|---|---|---|
| 1: | barely perceptible signal | |
| 3: | weak signal | |
| 5: | moderate signal | |
| 7: | strong signal | |
| 9: | extremely strong signal |
In contrast to the RST system, the signal strength is not measured with measuring devices, but is assessed purely visually using the waterfall display of the decoding software used .
Q - quality
| code | evaluation | |
|---|---|---|
| 1: | very broad spectrum ( splatter ) | |
| 3: | multiple visible, unwanted sideline pairs | |
| 5: | a clearly visible pair of sidelines | |
| 7: | a barely visible pair of sidelines | |
| 9: | clean signal - no visible side lines |
The quality is also assessed visually in the waterfall display.