Hi Dave,
Thanks for explaining. 600W is pretty good power already. Since the commercial amps are bricks it seems they must have good protection against sudden mismatches as well.
I remember when I had a coil in the antenna open, which was immediately followed by an exploding coax cable portion. The tubes didn't even flinch but in the 70's just the opening coil would have immediately destroyed even a small transistor amp because the SWR network wasn't fast enough to shut it down.
Regards, Joerg
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