| R |
Readability |
| 1 |
Unreadable |
| 2 |
Barely readable, occasional words distinguishable |
| 3 |
Readable with considerable difficulty |
| 4 |
Readable with practically no difficulty |
| 5 |
Perfectly readable |
| S |
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 |
| T |
Tone |
| 1 |
Sixty cycles or less, very rough and broad |
| 2 |
Very rough ac, very harsh and broad |
| 3 |
Rough ac tone, rectified but not filtered |
| 4 |
Rough note, some trace of filtering |
| 5 |
Filtered rectified ac, 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 |
