>So could someone please explain or point me towards some books/articles
>that talk about what happens exactly with voltages/currents at bad SWR?
To keep it real simple, depending on coax line length, ( node /
anti-node), the max voltage = sq root of the swr. IE: 2:1 swr. Max
voltage = 1.41 x normal (1:1 swr) swr.
1500 watts into 50 ohm dummy load = 5.5 amps into 50 ohms = 275 Vrms =
386 V peak.
With a 2:1 swr, rms voltage will rise to 386 vrms. Peak V will rise to
550 V peak.
Max rms current will also be sq root of the SWR. Into a DL, that's 5.5
amps with 1.5 kw and 1:1 swr.
With a 2:1 swr, RMS current rises to 7.78 amps.
You will not obtain max V or max I at the same time.
It's average current that melts stuff.....and peak V that arcs stuff.
Depending on power output, with typ tube amps, I would not go much past a
2:1 swr. Maybe 2.5:1 max.
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