40m Noise on panadapter

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  • Updated 8 months ago

Since setting up the flex I have had a weird base noiseline only on 40m. It was not straight like all the other bands but almost looked like 1/2 a sine wave repeating the whole way across the 40m band. It did not interfere much with reception yet every feature on the 6400m I used would not get rid of it. When I switched to dummy load for the receive antenna it subsided but still was there. I tried setting the RF Preamp at -8db did not even affect the sine wave but did affect the noise and signal riding on the sine wave.

Yesterday after trying Smartsdr for windows with my micro desktop and realizing in a short period of time that the case of the micro desktop was so hot I could not hardly touch it, I realized if I am going to use a computer with the 6400M it was not going to be that one.

I disconnected and removed the computer which was about 3 inches from the rig then I removed the power brick and cords which fed that computer and it went into the drawer of collectable stuff which I currently have no use for.

Well this morning when I hooked up my Heil Proset I noticed the 40m base noiseline was almost flat! Just a very very slight ripple yet. So apparently it was the power supply brick providing power to the computer I removed which was causing the sine wave.

Now all I need to do is find what is causing the remaining slight ripple on 40m.

I have soooo many wall warts and stuff connected all around my desk plugged into at least 3-4 power strips so it could be any one of them, another project for another day I guess ... so much to do and so little time, and the xyl says I cant retire for another 10 years!!!!

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Wayne

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Posted 8 months ago

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Bill -VA3WTB

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Take a look at this, good info.
https://www.dropbox.com/s/kffp92esffo...