READABILITY |
1 |
Unreadable |
2 |
Barely readable; only occasional words distinguishable |
3 |
Readable but with considerable difficulty |
4 |
Readable with practically no difficulty |
5 |
Perfectly readable |
SIGNAL STRENGTH |
1 |
Very faint signals |
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 |
A sixty-cycle hum is present on the signal. Very rough and raw to listen to |
2 |
Very rough, harsh and broad a.c. hum is present on the signal. |
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 note, no trace of ripple or modulation of any kind. |