> Guys, all I asked was whether I could do any harm to my
> transceiver by operating it into a high-SWR load, or at least one
> high enough to cause the output power to be folded back by the
> protective circuitry.
>
If the SWR causes excessive voltage in the PA, it will BLOW
the output transistors. If the SWR causses current in the PA,
it will cause excessive heat. Hopefully, the SWR protection
circuitry is designed to prevent both, especially the high
voltage scenario since that would be fatal. Excessive heat
(current) would also cause the cooling fan to turn on giving
you another clue. Since the transmitter still produces output,
it is safe to assume that excessive voltage was NOT present.
If these scenarios make you nervous, build an external antenna
tuner for 160M, or use your amplifier as a buffer. My 160M
elevated GP (140 ft) is seriously detuned when my 80M JA / SA
inverted vee is suspended from a crossarm at the top of the
tower (with isolated ladderline feedline). I still use it on 160M
with 1400W forward and 400W reflected. In fact, it 'feels' more
competitive with the additional top loading. The 3-500's in
my amp don't seem to mind and I'm happy to have worked
XZ0N, ZD9, and ZL9CI among others with that configuration.
Tom N4KG
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