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 20 M Noise level 
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Post Re: 20 M Noise level
Ok great thanks for clarifying.

I spent the morning , checking things over and tried a RX loop low to the ground ! Wow what a difference, I also put up a temporary dipole and that was amazing too.

The difference of having low noise is massive, such a pleasure to listen to the bands. I could hear weak signals so clear with a great signal to noise ratio.

I found the PSU to our fibre media converter making some very very low level noise on 160 and 40m, I also thought I found our shed to be radiating some sort of noise.

Very much enjoyed my day on the radio, until I popped the coax back on the vertical to seal the connection and the S3 of hash is back. Huuuuuuuggghhh i was sure I tested the vertical during the process and had good results.

Ah well off the pub I go lol , try again tomorrow to see if the vertical is much noisier and I forget to test it. Or did we turn something back on , or are the neighbours back in with something on.

Interestingly some of the noise from the fibre convertor seems to increase when the TV Coax is connected. I am thinking it must be going up the coax and out the TV antenna !? Fibre cable runs next to TV Coax i think.

At least i know what things should sound like now with no noise.


Sat Mar 30, 2024 4:56 pm
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 20 M Noise level 
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Location: Isle of Wight. IO90FQ. EU-120.
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Post Re: 20 M Noise level
Last night after the shop closed and turned the lights off. !5mtrs that looked to all intents to be dead sprang into life,
almost as if I had just plugged the antenna in.

Today as its open, the band looks dead again.

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Sun Mar 31, 2024 11:55 am
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 20 M Noise level 
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Post Re: 20 M Noise level
M0SWS wrote:
Ok great thanks for clarifying.

I spent the morning , checking things over and tried a RX loop low to the ground ! Wow what a difference, I also put up a temporary dipole and that was amazing too.

The difference of having low noise is massive, such a pleasure to listen to the bands. I could hear weak signals so clear with a great signal to noise ratio.

I found the PSU to our fibre media converter making some very very low level noise on 160 and 40m, I also thought I found our shed to be radiating some sort of noise.

Very much enjoyed my day on the radio, until I popped the coax back on the vertical to seal the connection and the S3 of hash is back. Huuuuuuuggghhh i was sure I tested the vertical during the process and had good results.

Ah well off the pub I go lol , try again tomorrow to see if the vertical is much noisier and I forget to test it. Or did we turn something back on , or are the neighbours back in with something on.

Interestingly some of the noise from the fibre convertor seems to increase when the TV Coax is connected. I am thinking it must be going up the coax and out the TV antenna !? Fibre cable runs next to TV Coax i think.

At least i know what things should sound like now with no noise.


If you're hoping for a zero noise level that will remain zero throughout the day yet still receive signal at the same strong signal strength that's never going to happen. Regarding the antenna comparisons swapping out the vertical for another with different characteristics, ie. isn't also omnidirectional or has a different angle of radiation due to being closer to the ground or whatever of course it's going to show a different meter reading but it's the signal to noise ratio should be your main goal.... not a more silent receive.
Here's a video which will hopefully explain better what I mean. That S5 noise on that same beam heading as i type is now showing 2S points instead of 5 and that's within a half hour window of making and uploading the video to typing this reply.
https://www.youtube.com/watch?v=ZZzS0jpi5OM&t=7s

https://www.qrz.com/db/BY0AC This is the station on the Vid, China has come a long way. ;)

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Sun Mar 31, 2024 1:08 pm
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 20 M Noise level 
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Post Re: 20 M Noise level
Gerry,

Interesting and thanks for the video.

I understand what you are saying regarding the signal to noise.

I wonder if you think your noise floor is natural or man made electrical ? No doubt a little mix of both. Although you look to have few neighbours ;-).

The challenge I see with the RFI is that it often brings an actual audible noise or harsh hash with it too. So it is harsh to listen too.

Thanks.

Sam


Sun Mar 31, 2024 4:15 pm
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 20 M Noise level 
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Post Re: 20 M Noise level
M0SWS wrote:
Gerry,

Interesting and thanks for the video.

I understand what you are saying regarding the signal to noise.

I wonder if you think your noise floor is natural or man made electrical ? No doubt a little mix of both. Although you look to have few neighbours ;-).

The challenge I see with the RFI is that it often brings an actual audible noise or harsh hash with it too. So it is harsh to listen too.

Thanks.

Sam


It's natural because my noise floor is dependent on atmospheric conditions. Trying to eradicate it would be like trying to null out rain static or hash experienced pointing the antenna towards an electrical storm.

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Sun Mar 31, 2024 4:33 pm
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 20 M Noise level 
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Post Re: 20 M Noise level
No chance here its S8/9 on 20 mtrs, damn shop. He closed up last night just after 10:15.
The bands all seemed to have life that I couldn't find 10 minutes earlier.

When the lights are of is about S2-3 noise floor, that I can live with.
80 & 40 mtrs are completely wiped out along with 6mtrs. when they are open and the lights are on.

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Sun Mar 31, 2024 5:16 pm
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