Len (K2IVX),
Look to old B&W in Bristol, PA (still there) for already made high power
resistors for antenna termination. They make a wierd 'folded doublet'
antenna that is real flat across the HF band. Magic - it has a 600 Ohm or
1200 Ohm resistor at the apex. The gain referenced to a tuned dipole is
nothing to write about.
Also, you could put a bunch of Cesiwid (formerly Carborundum) glo-bar
resistors in a small box with oil
to do this. Or air cool them. They are not inexpensive however. Would
recommend going to Fair Radio or Surplus Sales of Nebraska to look first.
If you do find Dale resistors, beware that if they are wirewound, you might
have trouble at 4 MHz getting them to be flat. Bird ususally uses a power
film on ceramic core, such as made by Altronics in Arkansas. They are
expensive elements to use also, probably even more than Cesiwid solid
carborundum resistors.
John
K5PRO
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