RST Explained

Yes, it is all about ham radio

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The RST System is used by ham radio operators to describe the strength and quality of a signal. It is used to give the transmitting station a signal report from the receiving station. Courage Center Handi-Ham members are encouraged to learn and use the RST system, in which numbers are given as ratings for each quality: readability, signal strength, and tone quality in the case of Morse code operation.  In this system, the lowest number is worst and the highest number is best.



2--Barely readable, occasional words distinguishable.

3--Readable with considerable difficulty.

4--Readable with practically no difficulty.

5--Perfectly readable.

Signal Strength:

1--Faint signals, barely perceptible.

2--Very weak signals.

3--Weak signals.

4--Fair signals.

5--Fairly good signals.

6--Good signals.

7--Moderately strong signals.

8--Strong signals.

9--Extremely strong signals.


1--Sixty cycle a.c or less, very rough and broad.

2--Very rough a.c., very harsh and broad.

3--Rough a.c. tone, rectified but not filtered.

4--Rough note, some trace of filtering.

5--Filtered rectified a.c. but strongly ripple-modulated.

6--Filtered tone, definite trace of ripple modulation.

7--Near pure tone, trace of ripple modulation.

8--Near perfect tone, slight trace of modulation.

9--Perfect tone, no trace of ripple or modulation of any kind.

If the signal has the characteristic steadiness of crystal control, add the letter X to the RST report. If there is a chirp, the letter C may be added to so indicate. Similarly for a click, add K. The above reporting system is used on both cw and voice, leaving out the "tone" report on voice.

This the end of the file.