McIntyre needed no FCC license to transmit on 8.971 kHz, since the Commission has not designated any allocations below 9 kHz — dubbed “the Dreamers’ Band.”
Dang.
McIntyre’s transmitter consisted of a Hewlett Packard HP 3586B selective level meter with tracking generator. The low-level generator output is amplified by a Wandel & Golterman A-160 level regulator, which feeds a Hafler P3000 stereo audio amplifier, which has been bridge connected for mono output. In this configuration, the P3000 is capable of putting out 400 W of audio into an 8 W load. McIntyre said the same generator and amplifier have been used on 137, 74, and 29 kHz experiments.
His antenna is essentially the same one he uses for 160 meters and for other LF experiments. For this experiment, however, it was equipped with a gigantic base-loading coil, which contains nearly a mile of wire. “The vertical wire is spaced 1.5 meters from the tower, hanging from an insulator 29 meters above ground,” McIntyre explained. “Top hat consists of about 170 meters of #18 Copperweld. Most of the top hat wires run about 7 to 20 meters over the top of a combination of oak and pine trees. Total antenna capacitance is close to 1200 pF.”
apftwb@lemmy.world 1 week ago
Dang.