1 -- Unreadable

2 -- Barely readable, occasional words distinguishable.

3 -- Readable with considerable difficulty.

4 -- Readable with practically nodifficulty.

5 -- Perfectly readable.

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.