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Re: QDX - output dropped from ~5W to ~2W

 

The SWR is always 1,0 to 1,2 ... the same as it was before.

I have already 4 BS170s on my desk, as I thought it might be one or two of them - now I'll exchange all four during the next couple of days.

Thanks a lot, Bruce!

Am 15.10.2024 um 15:39 schrieb Bruce Akhurst:

How are you changing antenna bands?? What SWR does each band see?? Do you have an ATU up there ?
If the same issue is seen feeding a dummy load then my money is on
1 BS170 failed (probably short, probably due to voltage or SWR) )
which took out the side of IC5 that was feeding it
and/or probably the other BS170 on that side.
So you are left with half a signal which is being tidied up by the LPF and giving you half power . .? ? ?If you have a scope check the signals on IC5 3 and 8 . .? ?Failing that compare the DC voltages on 3 vs 8 with a multimeter
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