d
Frequency in MHz
Wavelength in meters:
a.m. broadcast 1.8 3.5 7.0 14.0 21 28 50 . . .
600-200 160 80 40 20 15 10 6 . . .
----------------------------------------------------------------------
| . | . | . . .
very heavily attenuated | . | . | . . .
| less | . | . . .
attenuated . | . . .
| . | low | . . .
| . attenuation . . .
| . | . | little to no
| . | . | . attenuation . . .
| | . | . . .
------------------------------+-------+-------+-----------------------
| . | . . .
| . | . . .
heavily propagated . . . | . | . rapidly
(ground wave) (skip) | . | . decreasing . . .
| . | . . .
------------------------------+-------+-------+-----------------------
| . | . . .
these frequencies this one . . .
work mostly in the will go . . .
evenings . . . . . . . . . . . . during . these may . . .
the day . . .
| . | . . .
------------------------------+-------+-------+-----------------------
ASCII Description: The above table is in ASCII art — just happened to be lying around like that for about 16 years now (did it in Wordstar!). It is a tabular depiction of the relationship among frequency (wavelength), attenuation, and propagation: lower frequencies propagate (ground wave or skip) but are attenuated; higher frequencies are not attenuated but do not propagate, either; best choices are in the middle range of about 20 meters. [return to reference]
