Noise Bump on 60M Ch 2

ron4094
Posts: 22
Joined: Sun Nov 24, 2019 1:16 am

Noise Bump on 60M Ch 2

Postby ron4094 » Mon Jun 08, 2020 8:40 pm

I switched over to 60 meters for the first time on my Anan 7000 dle mk2 and noticed what appears to be a rather substantial noise bump on Ch 2. It appears to be FMing slightly and is also visible without my antenna connected. The attached image was taken with my dummy load connected.

Ron
WB2RON
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w-u-2-o
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Joined: Fri Mar 10, 2017 1:47 pm

Re: Noise Bump on 60M Ch 2

Postby w-u-2-o » Tue Jun 09, 2020 4:17 pm

That is almost certainly some noise from the internal switching power supply. On my 8000 I see exactly that down around 5310KHz.

While it's unfortunate that in your particular case the noise is impinging on one of the 60M channels, the good news is that it is most likely below the noise floor with an antenna attached.

If you look down around the 160M band you may find similar noisy spots. Some folks find them in-band. Again, I'm lucky in that my hardware puts them outside of the 160M band.

Some folks have added a bunch of bypass capacitors to their internal power supplies to mitigate these spots, but I wouldn't bother if they are below your noise floor.
ron4094
Posts: 22
Joined: Sun Nov 24, 2019 1:16 am

Re: Noise Bump on 60M Ch 2

Postby ron4094 » Tue Jun 09, 2020 5:27 pm

You're correct. With the antenna connected on 60 meters the bump is barely noticable above the noise floor. I just think that it's strange that spurs were not cleaned up prior to final design release. Anyway, this is certainly not an operating issue for me.

Ron
WB2RON

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