OK, let's do the math for a resonant dipole. (One operated on its fundamental
frequency.)
The center is 72 ohms theoretical, and if you droop it to an inverted Vee, it
might approach 50 ohms. And that depends on height above RF ground.
The end of a dipole well up in the air would be about 3000 ohms. This would
be the limit of mismatch practically speaking.
Thus, even the 100,000 ohm resistor would still be a factor of 3/100 of the
end impedance, and thus little power is involved. The whole premise was also
this goes on the side of the tuner toward your rig, (Low impedance side),
which should be operated close to ideal match after the first time you find
the appropriate settings by peaking the tuner on received noise, and before
you transmit power thru the tuner. Other than outright error, you don't have
to worry about the use of high value resistive impedance. Remember 2:1 SWR is
only 100 ohms, even a dreaded 4:1 is only 200 ohms, etc.
At 100 watts out of the rig, across 50 ohms, you only have about 70.7 volts.
At 1000 watts 707 volts, which says pick the appropriate voltage rated
resistor, the power would be miniscule for a 100,000 ohm bleeder but you want
adequate arc over rating across the ends of the resistor at kilowatt levels.
If you want to, you can up the resistor to 1,000,000 ohms, and it will still
bleed static charge but with a 10 times the time constant to bleed off any
charge.
If you are squeamish at kilowatt levels about sizing a resistor, a shunt choke
could be used, but it will vary in impedance and therefore effectiveness with
frequency. At the tuner input, remember it would be a shunt L creating a type
of pi net with the tuner built in C and shunt L of the Tee tuner. The
resistors should be carbon rather than wire wound also to prevent inductance
effects.
Gas tubes are fine, but don't fire typically until
the voltages are high enough to have fried a tender front end diode mixer.
This was one of the failings of the short lived QRP+ brand transceiver
product. (No front end protection on the early models.)
The example antenna was shown as a resonant dipole, but beams are even lower
impedance devices, thus their impedance at center even off frequency would not
approach the dipole end impedance.
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