Thanks for all the help to everyone. The spur on 1819 is gone for
now, hopefully permanently.
Now we have three NDB's in the SE USA and two more BC
stations to go, all were reported in he past few days directly to field
offices working in the area of the transmitters.
If anyone is bothered by an airport NDB, please call it in to the
ARRL or the FCC. You can identify an NDB by the constant
repeating of three letters (no numbers). They sometimes appear as
an exact image of the actual CW ID, since the transmitters have
separate carrier and tone oscillators in an early stage.
These transmitters are below the BC band, and generally have NO
filtering in any high power stages of the transmitters. They stupidly
depend on linear operation of several stages to NOT generate
strong harmonics, and what harmonics are there are supposedly
suppressed by a loading coil!!!
That's right, not a single low-pass filter anywhere after the
transistors in the output (which is clamped by zener diodes for
lightning protection)....and they are almost never tested properly.
73, Tom W8JI
W8JI@contesting.com
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