On Monday, January 14, 2019 12:48:04 PM you wrote:

> Hi Claudio,

>

> >...some people can't live without the SWR meter on the

> >transmission line: the harmonics not irradiated return toward

> >the Tx and the SWR meter show an high value: terrible!!!

> >

> >but if you have a LPF the SWR is also high BEFORE the filter

>

> If you have the usual configuration TX->LPF->SWR_Meter->Antenna

> the indicated SWR will NOT be spoiled by returning harmonics because

> they are attenuated by the LPF and reflected into the TX.

> So only extremely weak harmonics make it to the antenna.

> Their refeflection by the antenna does'nt change SWR measurably.

Yes Clemens, I agree.

I mean that without the LPF the SWR meter measure all the harmonics reflected by the antenna, so the SWR measured can be a lot higher and can be cause of MOSFETS failure.

I come from vacuum tube Tx and I can survive with high SWR if also the transmitter can ;-)

73

Claudio, IK2PII

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