How to send a Radio Report on CB Radio
An important part of most QSOs is knowing how well you are being received and often the best way to do this is to ask for a radio report from another station.
The standard signal reporting method for amateur radio is the RST (Readability-Signal Strength-Tone) system. The best signal report for CW (morse code) operation is RST 599. With voice, we don't use the reading for Tone and just give a RS report, a perfect signal on voice is RS 59 or just “five nine.” You’ll typically hear something like : “your signal report is five nine in North London.”
If you are good copy, you will usually get a “Five” for Readability. The Signal Strength is usually what the operator is reading on the Signal Meter of his receiver. Of course, with both CW and SSB, the S-Meter will be bouncing around a bit, so some interpretation is required.
More importantly, there is considerable variation in S-Meter calibration, so signal reports can vary from radio to radio. (S9 is commonly defined as 50 µV at the receiver input, with each S unit representing a 6 dB change in signal strength.) A 55 or 57 report indicates that the signal is very readable but the signal strength is not as strong as a 59 signal.
Most S Meters show an extended scale above S9 that is listed in terms of decibels. The scale may be marked with +10 dB, +20 dB, etc. indicating that the signal strength is that much stronger than S9. You’ll hear radio amateurs say something like “you are 5 9 plus 20 dB.” Or they may just say “you are 20 dB over.”
It is common for DX and contest stations to give out “rubber stamp” signal reports. Basically, they are trying to work as many stations as fast as possible and don’t want to be bothered with accurate signal reports, so everyone gets a 59 or 599 report.
You will also hear the classic Five Nine signal report on FM, which is basically saying “excellent signal.” While S Meters are often inconsistent on CW/SSB transceivers, they are almost universally poor on FM rigs. Most FM radios just give you an unlabeled bar graph that is only a relative indicator of signal strength. Usually, these are not labeled in terms of S units.
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.
