TABLE 2. Theshold for perception of rf sound (ambient noise level 70-
90 db).
Peak
Avg Peak Peak Magnetic
Power Power Electric Field
Trans- Frequency, Duty Cy. Density, Density Field amp.
mitter mc mw, cm2 mw, cm2 v cm turns, m
A 1,310 .0015 0.4 267 14 4
B 2,982 .0004 2.1 5,250 63 17
C 425 .0038 1.0 263 15 4
D 425 .007 1.9 271 14 4
E 425 .014 3.2 229 13 3
F 425 .028 7.1 254 14 4
FIG. 4. Threshold energy as a function of frequency of electromagnetic
energy (ambient noise level 70-90 db).
10000|---------|-------------|--------------|
|---------|-------------|--------------|
PEAK |---------|-------------|--------------|
POWER |---------|-------------|-------------*|
DENSITY |---------|-------------|------------*-|
(mw/cm2) | | | * |
|---------|-------------|---------*----|
| | | * |
|---------|-------------|------*-------|
| | | * |
| | | * |
| | | * |
1000|---------|-------------*--------------|
|---------|-----------*-|--------------|
|---------|---------*---|--------------|
| | * | |
|---------|-----*-------|--------------|
| * * * * * * * | |
|---------|-------------|--------------|
| | | |
| | | |
| | | |
100|---------|-------------|--------------|
200 1000 2000 3000
FREQUENCY (mc)
-37-