Noise in the center of Capturing signal, during the pass

Hi, I am noticing, at each Pass, there’s Noise in the center and in the beginning and in end.
Is this normal. Picture attached. Thanks.
NOAA 18 Pass

NOAA 15 Pass

NOAA 19 Pass

Here are the settings

2019-08-29%2021_54_12-RTL-SDR%20Controller

Hello, what is you antenna setup ???

It’s a V-Dipole Antenna - Thanks @F5MDY

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This morning

The beginning and end are likely just drop in S/N as the satellite is near the horizon. The noise in the middle could be a null in your antennas reception lobes.

–Roy
K3RLD

Thanks @K3RLD Roy. Can you explain a bit more please “The noise in the middle could be a null in your antennas reception lobes.”

The V dipole is a great (simple) starter antenna, but it is not perfect.
Every antenna has a ‘shape’ it projects into space. The most simple one to picture is a vertical antenna. The shape it picks up is like a donut. That’s why it is not very good for space work because there is a big hole at the top middle, bad for satellites.
Your V dipole is like two donuts, one on each arm. While the center of the donuts project up into space, there are nulls, or dead spots in pattern. Where those nulls are matches your noise bars. (Probably).
You can upgrade your antenna, or try changing the angle a little bit. (Granted, a bit hard for you to do with your brown plastic angle setter piece).

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Thank you @thebaldgeek -