On Tue, Feb 9, 2021 at 02:10 AM, Peter Ivanooff wrote:
PA - Tube with 1900 volts on Anode/ 0.5 A plate current (DC) when the PI
filter
is set to max output power on 3.65 Mhz..
LOAD - 250 watts non-inductive load up to 3 Ghz on a solid radiator (I had to
pause so as not to blow it) is heated to 80 degrees Celsius for 30 seconds
Nonstop test.The Choke NO - it remained relatively cold.
Just to get us "more scientific" and enable others to use and rely on your experience, would be great if you can provide "set up and measurements" in SI units instead of in descriptive statements :)
1) Power dissipation of the PA (tube) can be irelevantan - it only tells how much heat will dissipate inside the amplifier. Without knowing how much power was "send" by the power supply, or even better how efficient is the amp, we can't conculde how much power was sent to your dummy load
2) I suppose that your dummy load is 50 ohm
3) Stated power of the load (250W) does not tell much. It's usually "power rating for given duty cycle" (for example: 100W @1hr, 250W @1min, 1000W @2sec)
The most helpful will be if you can connect your oscilloscope to the dummy load (mind the max voltage prorated for frequency) and measure either "peak to peak" or "max" voltage.
Keep in mind that "p-p" (between + and - maximum) is double of "max" (zero to maximum).
From that, it will be easy to calculate the power your balun is handling as P = (Vmax/1.4)^2 / 50.
If you expect that that you have 250W delivered to your load, you should see Vpp = 2*1.4*sqrt(250*50) = 313V
