RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Post by glovisol » Wed Oct 31, 2018 7:53 pm

RECEIVING SYSTEM ASSESSMENT @ 3.8 MHz

Noise Floor assessment for the 3.8 MHz band is as follows:

Wavelength Wl @ 3.75 MHz: Wl = 300/3.75 = 80 m
Ratio L/Wl: R = 135/80 = 1.69
From "Beverage Antenna gain Vs. wavelength", Figure 1 in the cited reference: G = -2.5 dB referred to the isotropic.
Balun insertion loss is 0.5 dB. Total loss is 3 dB. To compare the measurement with data and criteria of Table 3, we must correct by adding 3.0 dB to measured noise values.

The graph shown below carries the raw measurements in ligt blue and the corrected measurement in red, compared to the noise leve ranges of "Rural" and "Quiet Rural". The Rural decile range extends for +/-3.5 dB, while the Quiet Rural range extends for +/- 3 dB. The noise peaks shown 22/10 to 25/10 and 28/10 to 29/10, caused by electrical activity due to stormy weather, are present at this frequency also.

In general, under average weather conditions, we can classify the receiving system under examination as located mid-way between Quiet Rural and Rural.
Attachments
2. Noise meas. 3.8 MHz.jpg
Two week Noise Floor measurement data @ 3.75 MHz
2. Noise meas. 3.8 MHz.jpg (352.69 KiB) Viewed 6222 times

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Post by glovisol » Fri Nov 02, 2018 1:23 pm

RECEIVING SYSTEM ASSESSMENT @ 7.2 MHz

Noise Floor assessment for the 7.2 MHz band is as follows:

Wavelength Wl @ 7.2 MHz: Wl = 300/7.2 = 43 m
Ratio L/Wl: R = 135/43 = 3.15
From "Beverage Antenna gain Vs. wavelength", Figure 1 in the cited reference: G = +1.5 dB referred to the isotropic.

Balun insertion loss is 0.5 dB and total gain is: 1.0 - 0.5 = 1.0 dB. Therefore the Noise Floor measurements taken with this antenna show a noise level of 1.0 dB more than the level we should have obtained if the measurement had been taken with an isotropic antenna. To compare the measurement with data and criteria of Table 3, we must correct by subtracting 1.0 dB to measured noise values.

The graph shown below carries the raw measurements in ligt blue and the corrected measurement in red, compared to the noise leve ranges of "Residential", "Rural" and "Quiet Rural". The Residential decile range extends for +/- 4 dB, the Rural range extends for +/- 3.5 db, while the Quiet Rural range extends for +/- 3 dB. The noise peaks shown 23/10 to 24/10 and 28/10 to 29/10, caused by electrical activity due to stormy weather, are present at this frequency also.

In general, under average weather conditions, we can classify the receiving system under examination as located in a Rural situation.
Attachments
3. Noise meas. 7.2 MHz.jpg
Two week Noise Floor measurement data @ 7.2 MHz
3. Noise meas. 7.2 MHz.jpg (330.79 KiB) Viewed 6172 times

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Post by glovisol » Sat Nov 03, 2018 7:58 pm

RECEIVING SYSTEM ASSESSMENT @ 14 MHz

Noise Floor assessment for the 14 MHz band is as follows:

Wavelength Wl @ 14 MHz: Wl = 300/14 = 21.4 m
Ratio L/Wl: R = 135/21.4 = 6.3
From "Beverage Antenna gain Vs. wavelength", Figure 1 in the cited reference: G = +5.0 dB referred to the isotropic.

Balun insertion loss is 0.5 dB and total gain is: 5.0 - 0.5 = 4.5 dB. Therefore the Noise Floor measurements taken with this antenna show a noise level of 4.5 dB more than the level we should have obtained if the measurement had been taken with an isotropic antenna. To compare the measurement with data and criteria of Table 3, we must correct by subtracting 4.5 dB to measured noise values.

The graph shown below carries the raw measurements in ligt blue and the corrected measurement in red, compared to the noise leve ranges of "Residential", "Rural" and "Quiet Rural". The Residential decile range extends for +/- 4 dB, the Rural range extends for +/- 3.5 db, while the Quiet Rural range extends for +/- 3 dB. The noise peaks shown 23/10 to 26/10 and 28/10 to 29/10, caused by electrical activity due to stormy weather, are present at this frequency also.

In general, under average weather conditions, we can classify the receiving system under examination as located mid-way between Rural and Quiet Rural situations.
Attachments
4. Noise meas. 14 MHz.jpg
Two week Noise Floor measurement data @ 14 MHz
4. Noise meas. 14 MHz.jpg (319.96 KiB) Viewed 6101 times

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Post by glovisol » Tue Nov 06, 2018 6:43 am

RECEIVING SYSTEM ASSESSMENT @ 21.5 MHz

Noise Floor assessment for the 21 MHz band is as follows:

Wavelength Wl @ 21.5 MHz: Wl = 300/21.5 = 13.9 m
Ratio L/Wl: R = 135/13.9 = 9.7
From "Beverage Antenna gain Vs. wavelength", at the extreme of Figure 1 in the cited reference, we extrapolate: G = +7.5 dB referred to the isotropic.

Balun insertion loss is 0.5 dB and total gain is: 7.5 - 0.5 = 7 dB. Therefore the Noise Floor measurements taken with this antenna show a noise level of 7.0 dB more than the level we should have obtained if the measurement had been taken with an isotropic antenna. To compare the measurement with data and criteria of Table 3, we must correct by subtracting 7.0 dB to measured noise values.

The graph shown below carries the raw measurements in ligt blue and the corrected measurement in red, compared to the noise leve ranges of "Residential", "Rural" and "Quiet Rural". The Residential decile range extends for +/- 4 dB, the Rural range extends for +/- 3.5 db, while the Quiet Rural range extends for +/- 3 dB. The noise peak shown 23/10 to 26/10, caused by electrical activity due to stormy weather, are present at this frequency also.

In general, under average weather conditions, we can classify the receiving system under examination as located in the Rural situation.
Attachments
5. Noise meas. 21.5 MHz.jpg
Two week Noise Floor measurement data @ 21.5 MHz
5. Noise meas. 21.5 MHz.jpg (342.88 KiB) Viewed 5992 times

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Post by glovisol » Wed Nov 07, 2018 1:15 pm

RECEIVING SYSTEM ASSESSMENT @ 29 MHz

Noise Floor assessment for the 28/29 MHz band is as follows:

Wavelength Wl @ 29.0 MHz: Wl = 300/21.5 = 10,34 m
Ratio L/Wl: R = 135/13.34 = 13
Figure 1 in the cited reference does not go all the way up to 13 length to Wavelengt ratio, so I consider a worst case guess of : G = +8 dB referred to the isotropic.

Balun insertion loss is 0.5 dB and total gain is: 8 - 0.5 = 7.5 dB. Therefore the Noise Floor measurements taken with this antenna show a noise level of 7.5 dB more than the level we should have obtained if the measurement had been taken with an isotropic antenna. To compare the measurement with data and criteria of Table 3, we must correct by subtracting 7.5 dB to measured noise values.

The graph shown below carries the raw measurements in ligt blue and the corrected measurement in red, compared to the noise leve ranges of "Residential", "Rural" and "Quiet Rural". The Residential decile range extends for +/- 4 dB, the Rural range extends for +/- 3.5 db, while the Quiet Rural range extends for +/- 3 dB. The noise peak shown 23/10 to 26/10, caused by electrical activity due to stormy weather, are present at this frequency also.

In general, under average weather conditions, we can classify the receiving system under examination as located between the Rural and Quiet Rural situations.
Attachments
Noise Floor statistics 2.jpg
Average measured and corrected Noise Floor
Noise Floor statistics 2.jpg (247.47 KiB) Viewed 5951 times
6. Noise meas. 29 MHz.jpg
Two week Noise Floor measurement data @ 29.0 MHz
6. Noise meas. 29 MHz.jpg (357.07 KiB) Viewed 5955 times

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Post by glovisol » Fri Nov 16, 2018 9:15 am

NOISE FLOOR DATA FOR THE FIRST 15 NOVEMBER DAYS

In this and subsequent posts I am uploading data measured 1 to 15 November. Previous data taken in October shows the noise floor increase and instability due to stormy weather in Southern Europe, which caused big damages, as reported by the International Press. The last 15 days have seen weather gradually going to calmer and calmer states and this reflects on the settled noise floor data recorded in the second week.
Attachments
1-2. Noise meas. 1.8 MHz.jpg
Two week Noise Floor measurement data @ 1.8 MHz
1-2. Noise meas. 1.8 MHz.jpg (300.81 KiB) Viewed 5781 times
2-2. Noise meas. 3.8 MHz.jpg
Two week Noise Floor measurement data @ 3.75 MHz
2-2. Noise meas. 3.8 MHz.jpg (343.19 KiB) Viewed 5782 times

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Post by glovisol » Sat Nov 17, 2018 7:45 am

NOISE FLOOR DATA FOR THE FIRST 15 NOVEMBER DAYS

Collected data for 7 and 14 MHz
Attachments
3-2. Noise meas. 7.2 MHz.jpg
Two week Noise Floor measurement data @ 7 MHz
3-2. Noise meas. 7.2 MHz.jpg (314.18 KiB) Viewed 5745 times
4-2. Noise meas. 14 MHz.jpg
Two week Noise Floor measurement data @ 14 MHz
4-2. Noise meas. 14 MHz.jpg (315.41 KiB) Viewed 5745 times

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Post by glovisol » Mon Nov 19, 2018 9:39 am

NOISE FLOOR DATA FOR THE FIRST 15 NOVEMBER DAYS

Collected data for 21 and 29 MHz
Attachments
Noise Floor statistics 3.jpg
Average measured and corrected Noise Floor
Noise Floor statistics 3.jpg (230.02 KiB) Viewed 5662 times
5-2. Noise meas. 21.5 MHz.jpg
Two week Noise Floor measurement data @ 21.5 MHz
5-2. Noise meas. 21.5 MHz.jpg (336.26 KiB) Viewed 5668 times
6-2. Noise meas. 29 MHz.jpg
Two week Noise Floor measurement data @ 29 MHz
6-2. Noise meas. 29 MHz.jpg (337.88 KiB) Viewed 5668 times

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Post by glovisol » Tue Dec 18, 2018 6:43 pm

NOISE FLOOR DATA FOR THE FIRST 15 DECEMBER DAYS
Attachments
1.3 Noise meas. 1.8 MHz.jpg
Two week Noise Floor measurement data @ 1.8 MHz
1.3 Noise meas. 1.8 MHz.jpg (140.59 KiB) Viewed 4602 times
2-3 Noise meas. 3.8 MHz.jpg
Two week Noise Floor measurement data @ 3.8 MHz
2-3 Noise meas. 3.8 MHz.jpg (152.88 KiB) Viewed 4602 times

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Post by glovisol » Wed Dec 19, 2018 8:20 am

NOISE FLOOR DATA FOR THE FIRST 15 DECEMBER DAYS
Attachments
3-3. Noise meas. 7.2 MHz.jpg
Two week Noise Floor measurement data @ 7.2 MHz
3-3. Noise meas. 7.2 MHz.jpg (146.82 KiB) Viewed 4564 times
4-3 Noise meas. 14 MHz.jpg
Two week Noise Floor measurement data @ 14 MHz
4-3 Noise meas. 14 MHz.jpg (111.22 KiB) Viewed 4564 times

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