Signal Reports in Ham Radio

Signal reports are sometimes requested by operators who are testing a radio. Sometimes friendly operators will offer a signal report even if you don't ask for one. I usually get an unsolicited signal report if it is difficult to copy my voice transmission through a repeater.

The etiquette when using a repeater seems to be using plain English. So you might give or receive signal reports such as "I can hear you just fine", "your voice sounds strange" or "I can barely hear you and there is a lot of static". Problems with your transmission will often be followed by questions about your radio, its configuration and advice about how you may be able to improve your signal and readability.

Communication over great distances usually involve a more nerdy signal report with two or more numbers and maybe letters.

Source: ARRL

The RST System:

Readability
1. Unreadable
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.

Tone
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.