From: [email protected] [mailto:[email protected]] On Behalf Of Spence M0STO via groups.io
Sent: Wednesday, January 05, 2022 3:56 AM
To: [email protected]
Subject: [YaesuFT847] S9 noise on HF with or without antenna

?

Dear Group, I have a bit of a strange question. My FT847 has nothing but S9 of noise on HF (I work mostly satellite these days so only just noticed it). I tried all bands but seem to be blighted with an S9 signal with or without the antenna connected. The other issue is when I tune to a strong AM station in the lower broadcast band 2.2mhz seemed to be the strongest +50db on AM but the audio is dreadful and sounds splattered, clipped and inaudiable. I have been using a passive loop on HF and I’m fearing DC or a strong signal has landed in the front end and done damage.?

Before I tear my radio apart to resolve this I wondered if anyone had pointers. I know the FT897 used to suffer with S9 all the time due to the 455khz ceramic filters going bad but don’t think the FT847 uses them.

? Any help would be really appreciated.

thanks in advanced,

de Spence M0STO?

see below the test gear on hand to resolve this.

test gear:
Marconi 2955 radio test set
Marconi 2022 Signal Generator
Rigol DSA1030A spectrum analyser
Phillips 3833 60mhz Scope
AF generator?
VVM
logic probe etc.
GDO