QO-100 Finally!


Simon Brown
 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Matthias Bopp
 

Excellent.

 

Yes tuning the dish and feed can be tedious …

 

Congratulations getting it all right now

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 15:22
An: 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: [SDR-Radio] QO-100 Finally!

 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


--

- + - + -

Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Simon Brown
 

Indeed,

 

LNB skew, offset from focal point etc – gained ~1.5dB. Elevation 7dB at least.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 14:35
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Excellent.

 

Yes tuning the dish and feed can be tedious …

 

Congratulations getting it all right now

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 15:22
An: 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: [SDR-Radio] QO-100 Finally!

 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


--

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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--
- + - + -
Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Matthias Bopp
 

My 1.8m dish is quite deep (f/D=0.29)

 

When I first did some preliminary testing I had it adjusted in 15 minutes and the results were great.

 

I assumed that I might get even better results when everything was refurbished and at its final position.

 

When I tried there (on top of the roof of my garage) it took me more than 2 hours to align it and just get back to
the point where I had it during the preliminary test. Finally I managed to squeeze out another 1-2 dBs.

 

The good news is that my dish is now up and running about 2 years and the results are still the same …

 

By the way fine tuning is only possible with a DATV receiver tuned to the QO-100 WB beacon.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:06
An: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Indeed,

 

LNB skew, offset from focal point etc – gained ~1.5dB. Elevation 7dB at least.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 14:35
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Excellent.

 

Yes tuning the dish and feed can be tedious …

 

Congratulations getting it all right now

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 15:22
An: 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: [SDR-Radio] QO-100 Finally!

 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


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--

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Simon Brown
 

Hi,

 

Now I can see the ‘Bloom’ of the NB transponder I’ll look at receiving DATV, I have no idea where to start!

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:17
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

My 1.8m dish is quite deep (f/D=0.29)

 

When I first did some preliminary testing I had it adjusted in 15 minutes and the results were great.

 

I assumed that I might get even better results when everything was refurbished and at its final position.

 

When I tried there (on top of the roof of my garage) it took me more than 2 hours to align it and just get back to
the point where I had it during the preliminary test. Finally I managed to squeeze out another 1-2 dBs.

 

The good news is that my dish is now up and running about 2 years and the results are still the same …

 

By the way fine tuning is only possible with a DATV receiver tuned to the QO-100 WB beacon.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:06
An: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Indeed,

 

LNB skew, offset from focal point etc – gained ~1.5dB. Elevation 7dB at least.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 14:35
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Excellent.

 

Yes tuning the dish and feed can be tedious …

 

Congratulations getting it all right now

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 15:22
An: 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: [SDR-Radio] QO-100 Finally!

 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


--

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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--

- + - + -

Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--
- + - + -
Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Matthias Bopp
 

Hi Simon,

 

with your nice dish you should see the NB transponder noise rolling by about 5-6 dB.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:25
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Hi,

 

Now I can see the ‘Bloom’ of the NB transponder I’ll look at receiving DATV, I have no idea where to start!

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:17
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

My 1.8m dish is quite deep (f/D=0.29)

 

When I first did some preliminary testing I had it adjusted in 15 minutes and the results were great.

 

I assumed that I might get even better results when everything was refurbished and at its final position.

 

When I tried there (on top of the roof of my garage) it took me more than 2 hours to align it and just get back to
the point where I had it during the preliminary test. Finally I managed to squeeze out another 1-2 dBs.

 

The good news is that my dish is now up and running about 2 years and the results are still the same …

 

By the way fine tuning is only possible with a DATV receiver tuned to the QO-100 WB beacon.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:06
An: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Indeed,

 

LNB skew, offset from focal point etc – gained ~1.5dB. Elevation 7dB at least.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 14:35
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Excellent.

 

Yes tuning the dish and feed can be tedious …

 

Congratulations getting it all right now

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 15:22
An: 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: [SDR-Radio] QO-100 Finally!

 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


--

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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--

- + - + -

Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--

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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Simon Brown
 

Hi,

 

I do. I expect it’s big enough to receive DATV. For transmit I only have ~6W max into the dish after feeder loss.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:27
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Hi Simon,

 

with your nice dish you should see the NB transponder noise rolling by about 5-6 dB.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:25
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Hi,

 

Now I can see the ‘Bloom’ of the NB transponder I’ll look at receiving DATV, I have no idea where to start!

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:17
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

My 1.8m dish is quite deep (f/D=0.29)

 

When I first did some preliminary testing I had it adjusted in 15 minutes and the results were great.

 

I assumed that I might get even better results when everything was refurbished and at its final position.

 

When I tried there (on top of the roof of my garage) it took me more than 2 hours to align it and just get back to
the point where I had it during the preliminary test. Finally I managed to squeeze out another 1-2 dBs.

 

The good news is that my dish is now up and running about 2 years and the results are still the same …

 

By the way fine tuning is only possible with a DATV receiver tuned to the QO-100 WB beacon.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:06
An: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Indeed,

 

LNB skew, offset from focal point etc – gained ~1.5dB. Elevation 7dB at least.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 14:35
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Excellent.

 

Yes tuning the dish and feed can be tedious …

 

Congratulations getting it all right now

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 15:22
An: 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: [SDR-Radio] QO-100 Finally!

 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


--

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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--

- + - + -

Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--

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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--
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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Simon Brown
 

FWIW here’s what I see. I tuned to the WB transponder – no signals.

 

I have no idea how good my LNB is.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:27
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Hi Simon,

 

with your nice dish you should see the NB transponder noise rolling by about 5-6 dB.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:25
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Hi,

 

Now I can see the ‘Bloom’ of the NB transponder I’ll look at receiving DATV, I have no idea where to start!

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:17
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

My 1.8m dish is quite deep (f/D=0.29)

 

When I first did some preliminary testing I had it adjusted in 15 minutes and the results were great.

 

I assumed that I might get even better results when everything was refurbished and at its final position.

 

When I tried there (on top of the roof of my garage) it took me more than 2 hours to align it and just get back to
the point where I had it during the preliminary test. Finally I managed to squeeze out another 1-2 dBs.

 

The good news is that my dish is now up and running about 2 years and the results are still the same …

 

By the way fine tuning is only possible with a DATV receiver tuned to the QO-100 WB beacon.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:06
An: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Indeed,

 

LNB skew, offset from focal point etc – gained ~1.5dB. Elevation 7dB at least.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 14:35
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Excellent.

 

Yes tuning the dish and feed can be tedious …

 

Congratulations getting it all right now

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 15:22
An: 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: [SDR-Radio] QO-100 Finally!

 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


--

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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--

- + - + -

Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--

- + - + -

Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--
- + - + -
Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Matthias Bopp
 

For sure you will be able to receive DATV

 

I can do it with my 60cm portable dish

 

However with that small dish I can only receive the stronger signals and the MER of the beacon is only about 6.1dB

 

With the 1.8m dish the MER of the beacon is about 11.8dB

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:31
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Hi,

 

I do. I expect it’s big enough to receive DATV. For transmit I only have ~6W max into the dish after feeder loss.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:27
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Hi Simon,

 

with your nice dish you should see the NB transponder noise rolling by about 5-6 dB.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:25
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Hi,

 

Now I can see the ‘Bloom’ of the NB transponder I’ll look at receiving DATV, I have no idea where to start!

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:17
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

My 1.8m dish is quite deep (f/D=0.29)

 

When I first did some preliminary testing I had it adjusted in 15 minutes and the results were great.

 

I assumed that I might get even better results when everything was refurbished and at its final position.

 

When I tried there (on top of the roof of my garage) it took me more than 2 hours to align it and just get back to
the point where I had it during the preliminary test. Finally I managed to squeeze out another 1-2 dBs.

 

The good news is that my dish is now up and running about 2 years and the results are still the same …

 

By the way fine tuning is only possible with a DATV receiver tuned to the QO-100 WB beacon.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:06
An: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Indeed,

 

LNB skew, offset from focal point etc – gained ~1.5dB. Elevation 7dB at least.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 14:35
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Excellent.

 

Yes tuning the dish and feed can be tedious …

 

Congratulations getting it all right now

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 15:22
An: 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: [SDR-Radio] QO-100 Finally!

 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


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--

- + - + -

Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--

- + - + -

Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


--

- + - + -

Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Matthias Bopp
 

There was no attachment / picture attached to your Email.

 

You know that the polarization of the WB tpx is orthogonal to the NB tpx !?

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:37
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

FWIW here’s what I see. I tuned to the WB transponder – no signals.

 

I have no idea how good my LNB is.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:27
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Hi Simon,

 

with your nice dish you should see the NB transponder noise rolling by about 5-6 dB.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:25
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Hi,

 

Now I can see the ‘Bloom’ of the NB transponder I’ll look at receiving DATV, I have no idea where to start!

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:17
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

My 1.8m dish is quite deep (f/D=0.29)

 

When I first did some preliminary testing I had it adjusted in 15 minutes and the results were great.

 

I assumed that I might get even better results when everything was refurbished and at its final position.

 

When I tried there (on top of the roof of my garage) it took me more than 2 hours to align it and just get back to
the point where I had it during the preliminary test. Finally I managed to squeeze out another 1-2 dBs.

 

The good news is that my dish is now up and running about 2 years and the results are still the same …

 

By the way fine tuning is only possible with a DATV receiver tuned to the QO-100 WB beacon.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:06
An: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Indeed,

 

LNB skew, offset from focal point etc – gained ~1.5dB. Elevation 7dB at least.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 14:35
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Excellent.

 

Yes tuning the dish and feed can be tedious …

 

Congratulations getting it all right now

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 15:22
An: 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: [SDR-Radio] QO-100 Finally!

 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


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Attachments:


Simon Brown
 

Ah,

 

Yes – I realised that polarisation is different, that’s my problem. Maybe anti-virus removed the screenshot?

 

Try this: https://www.dropbox.com/s/pwyh4we0vpaeeea/Screenshot-2021-04-01-153600.jpeg?dl=0

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:46
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

There was no attachment / picture attached to your Email.

 

You know that the polarization of the WB tpx is orthogonal to the NB tpx !?

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:37
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

FWIW here’s what I see. I tuned to the WB transponder – no signals.

 

I have no idea how good my LNB is.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:27
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Hi Simon,

 

with your nice dish you should see the NB transponder noise rolling by about 5-6 dB.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:25
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Hi,

 

Now I can see the ‘Bloom’ of the NB transponder I’ll look at receiving DATV, I have no idea where to start!

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 15:17
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

My 1.8m dish is quite deep (f/D=0.29)

 

When I first did some preliminary testing I had it adjusted in 15 minutes and the results were great.

 

I assumed that I might get even better results when everything was refurbished and at its final position.

 

When I tried there (on top of the roof of my garage) it took me more than 2 hours to align it and just get back to
the point where I had it during the preliminary test. Finally I managed to squeeze out another 1-2 dBs.

 

The good news is that my dish is now up and running about 2 years and the results are still the same …

 

By the way fine tuning is only possible with a DATV receiver tuned to the QO-100 WB beacon.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 16:06
An: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Indeed,

 

LNB skew, offset from focal point etc – gained ~1.5dB. Elevation 7dB at least.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 01 April 2021 14:35
To: main@SDR-Radio.groups.io; 'SDR-Radio' <SDR-Radio@groups.io>
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Excellent.

 

Yes tuning the dish and feed can be tedious …

 

Congratulations getting it all right now

 

Regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Donnerstag, 1. April 2021 15:22
An: 'SDR-Radio' <SDR-Radio@groups.io>
Betreff: [SDR-Radio] QO-100 Finally!

 

So,

 

I’ve had my dish for two years I think, anyway I’ve never been happy with the received signal strength. I finally around to aligning it today – increased the SNR of the beacons by 8dB, what a difference! Being a 1.4m prime focus dish the 3dB beamwidth is quite small.

 

Woot – Woot!

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 


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Attachments:


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Mike Willis
 

I can receive my own DATV signals sent with under 1 watt. I have a 2.4m dish, That is equivalent to 4W for a 1.2m dish so Simon will have enough EIRP. On receive the difference between a 2.4m and 1.2m dish is under a dB. This is because you are receiving the transponder noise floor and the link limited by the SNR on the uplink. A 30m dish would only be a dB better. Diminishing returns. Simon's dish is in between these so should be getting around 11 dB MER on the DATV beacon. There are various reasons this might not happen, dosh pointing and focus being two but phase noise being a third. Knowing what he has I would think the dish might not be totally optimised. It is easy to tell, measure the noise floor of the narrow band transponder relative to the band just below, there should be an uplift. for me it is nearly 10 dB. for a 1.2m dish it should be more than 4 dB, for Simon perhaps 6 dB.



Mike


Simon Brown
 

Mike,

 

I see 5 to 6dB. I can’t put 18v into my LNB for vertical polarisation, that’ll be the main problem.

 

I can probably squeeze 1 dB more out of my system, I may do that if I ever have time.

 

What’s the NF for a LNB? I’m using the Single Opticum LSP-02G.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike Willis
Sent: 02 April 2021 09:57
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

I can receive my own DATV signals sent with under 1 watt. I have a 2.4m dish, That is equivalent to 4W for a 1.2m dish so Simon will have enough EIRP. On receive the difference between a 2.4m and 1.2m dish is under a dB. This is because you are receiving the transponder noise floor and the link limited by the SNR on the uplink. A 30m dish would only be a dB better. Diminishing returns. Simon's dish is in between these so should be getting around 11 dB MER on the DATV beacon. There are various reasons this might not happen, dosh pointing and focus being two but phase noise being a third. Knowing what he has I would think the dish might not be totally optimised. It is easy to tell, measure the noise floor of the narrow band transponder relative to the band just below, there should be an uplift. for me it is nearly 10 dB. for a 1.2m dish it should be more than 4 dB, for Simon perhaps 6 dB.


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Simon Brown
 

Ah,

 

My LNB has a NF of 0.1dB (sceptical).

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown
Sent: 02 April 2021 11:39
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Mike,

 

I see 5 to 6dB. I can’t put 18v into my LNB for vertical polarisation, that’ll be the main problem.

 

I can probably squeeze 1 dB more out of my system, I may do that if I ever have time.

 

What’s the NF for a LNB? I’m using the Single Opticum LSP-02G.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike Willis
Sent: 02 April 2021 09:57
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

I can receive my own DATV signals sent with under 1 watt. I have a 2.4m dish, That is equivalent to 4W for a 1.2m dish so Simon will have enough EIRP. On receive the difference between a 2.4m and 1.2m dish is under a dB. This is because you are receiving the transponder noise floor and the link limited by the SNR on the uplink. A 30m dish would only be a dB better. Diminishing returns. Simon's dish is in between these so should be getting around 11 dB MER on the DATV beacon. There are various reasons this might not happen, dosh pointing and focus being two but phase noise being a third. Knowing what he has I would think the dish might not be totally optimised. It is easy to tell, measure the noise floor of the narrow band transponder relative to the band just below, there should be an uplift. for me it is nearly 10 dB. for a 1.2m dish it should be more than 4 dB, for Simon perhaps 6 dB.


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Charles Suckling
 

Hi Simon

Can you physically rotate the LNB?

Charlie


On Fri, 2 Apr 2021 at 12:39, Simon Brown <simon@...> wrote:

Mike,

 

I see 5 to 6dB. I can’t put 18v into my LNB for vertical polarisation, that’ll be the main problem.

 

I can probably squeeze 1 dB more out of my system, I may do that if I ever have time.

 

What’s the NF for a LNB? I’m using the Single Opticum LSP-02G.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike Willis
Sent: 02 April 2021 09:57
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

I can receive my own DATV signals sent with under 1 watt. I have a 2.4m dish, That is equivalent to 4W for a 1.2m dish so Simon will have enough EIRP. On receive the difference between a 2.4m and 1.2m dish is under a dB. This is because you are receiving the transponder noise floor and the link limited by the SNR on the uplink. A 30m dish would only be a dB better. Diminishing returns. Simon's dish is in between these so should be getting around 11 dB MER on the DATV beacon. There are various reasons this might not happen, dosh pointing and focus being two but phase noise being a third. Knowing what he has I would think the dish might not be totally optimised. It is easy to tell, measure the noise floor of the narrow band transponder relative to the band just below, there should be an uplift. for me it is nearly 10 dB. for a 1.2m dish it should be more than 4 dB, for Simon perhaps 6 dB.


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Simon Brown
 

Hi,

 

Yes – I did optimise it by 1dB. I’m seeing a 5 to 6dB bloom which agrees with the expected results given my dish so the hardware’s OK. Rotating just for DATV is a pain at the moment – I’m very happy just to have the dish pointing at QO-100 and receiving decent signals for a change.

 

No time atm, as the weather’s good I must wash all my windows.

 

What I wat to do is determine why I can’t just write software for DVB-S2 / whatever, but looking at the spec. it’s quite some project!

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Charles Suckling
Sent: 02 April 2021 11:42
To: main@sdr-radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Hi Simon

 

Can you physically rotate the LNB?

 

Charlie

 

 

On Fri, 2 Apr 2021 at 12:39, Simon Brown <simon@...> wrote:

Mike,

 

I see 5 to 6dB. I can’t put 18v into my LNB for vertical polarisation, that’ll be the main problem.

 

I can probably squeeze 1 dB more out of my system, I may do that if I ever have time.

 

What’s the NF for a LNB? I’m using the Single Opticum LSP-02G.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike Willis
Sent: 02 April 2021 09:57
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

I can receive my own DATV signals sent with under 1 watt. I have a 2.4m dish, That is equivalent to 4W for a 1.2m dish so Simon will have enough EIRP. On receive the difference between a 2.4m and 1.2m dish is under a dB. This is because you are receiving the transponder noise floor and the link limited by the SNR on the uplink. A 30m dish would only be a dB better. Diminishing returns. Simon's dish is in between these so should be getting around 11 dB MER on the DATV beacon. There are various reasons this might not happen, dosh pointing and focus being two but phase noise being a third. Knowing what he has I would think the dish might not be totally optimised. It is easy to tell, measure the noise floor of the narrow band transponder relative to the band just below, there should be an uplift. for me it is nearly 10 dB. for a 1.2m dish it should be more than 4 dB, for Simon perhaps 6 dB.


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Matthias Bopp
 

Hi Simon,

 

forget those BS numbers of 0.1dB noise figure for LNBs.

 

If you just look up the NF of the transistors used in the LNBs they are typically above 0.5dB at 11GHz.

 

I would guess your LNB has a noise figure of about 0.8dB or worse.

 

Which is still a good number for a PLL based low noise downconverter which costs less than 10 Euros.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Freitag, 2. April 2021 12:40
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Ah,

 

My LNB has a NF of 0.1dB (sceptical).

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown
Sent: 02 April 2021 11:39
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Mike,

 

I see 5 to 6dB. I can’t put 18v into my LNB for vertical polarisation, that’ll be the main problem.

 

I can probably squeeze 1 dB more out of my system, I may do that if I ever have time.

 

What’s the NF for a LNB? I’m using the Single Opticum LSP-02G.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike Willis
Sent: 02 April 2021 09:57
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

I can receive my own DATV signals sent with under 1 watt. I have a 2.4m dish, That is equivalent to 4W for a 1.2m dish so Simon will have enough EIRP. On receive the difference between a 2.4m and 1.2m dish is under a dB. This is because you are receiving the transponder noise floor and the link limited by the SNR on the uplink. A 30m dish would only be a dB better. Diminishing returns. Simon's dish is in between these so should be getting around 11 dB MER on the DATV beacon. There are various reasons this might not happen, dosh pointing and focus being two but phase noise being a third. Knowing what he has I would think the dish might not be totally optimised. It is easy to tell, measure the noise floor of the narrow band transponder relative to the band just below, there should be an uplift. for me it is nearly 10 dB. for a 1.2m dish it should be more than 4 dB, for Simon perhaps 6 dB.


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Simon Brown
 

Yes,

 

That’s what I thought. It would be nice to have a more stable LNB but I’m not going to build a POTY at the moment, no time.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 02 April 2021 12:25
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Hi Simon,

 

forget those BS numbers of 0.1dB noise figure for LNBs.

 

If you just look up the NF of the transistors used in the LNBs they are typically above 0.5dB at 11GHz.

 

I would guess your LNB has a noise figure of about 0.8dB or worse.

 

Which is still a good number for a PLL based low noise downconverter which costs less than 10 Euros.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Freitag, 2. April 2021 12:40
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Ah,

 

My LNB has a NF of 0.1dB (sceptical).

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown
Sent: 02 April 2021 11:39
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Mike,

 

I see 5 to 6dB. I can’t put 18v into my LNB for vertical polarisation, that’ll be the main problem.

 

I can probably squeeze 1 dB more out of my system, I may do that if I ever have time.

 

What’s the NF for a LNB? I’m using the Single Opticum LSP-02G.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike Willis
Sent: 02 April 2021 09:57
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

I can receive my own DATV signals sent with under 1 watt. I have a 2.4m dish, That is equivalent to 4W for a 1.2m dish so Simon will have enough EIRP. On receive the difference between a 2.4m and 1.2m dish is under a dB. This is because you are receiving the transponder noise floor and the link limited by the SNR on the uplink. A 30m dish would only be a dB better. Diminishing returns. Simon's dish is in between these so should be getting around 11 dB MER on the DATV beacon. There are various reasons this might not happen, dosh pointing and focus being two but phase noise being a third. Knowing what he has I would think the dish might not be totally optimised. It is easy to tell, measure the noise floor of the narrow band transponder relative to the band just below, there should be an uplift. for me it is nearly 10 dB. for a 1.2m dish it should be more than 4 dB, for Simon perhaps 6 dB.


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Ryan Butler
 

Might check out this page:


It's for EME but same band,same principal, took one of these $5 LNBs and modified it with an SMA jack instead of the crystal to inject something stable from the shack for the LO.

Ryan, NF0T


On Fri, Apr 2, 2021 at 6:47 AM Simon Brown <simon@...> wrote:

Yes,

 

That’s what I thought. It would be nice to have a more stable LNB but I’m not going to build a POTY at the moment, no time.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Matthias Bopp
Sent: 02 April 2021 12:25
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Hi Simon,

 

forget those BS numbers of 0.1dB noise figure for LNBs.

 

If you just look up the NF of the transistors used in the LNBs they are typically above 0.5dB at 11GHz.

 

I would guess your LNB has a noise figure of about 0.8dB or worse.

 

Which is still a good number for a PLL based low noise downconverter which costs less than 10 Euros.

 

Kind regards

 

Matthias

 

www.dd1us.de

 

 

Von: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> Im Auftrag von Simon Brown
Gesendet: Freitag, 2. April 2021 12:40
An: main@SDR-Radio.groups.io
Betreff: Re: [SDR-Radio] QO-100 Finally!

 

Ah,

 

My LNB has a NF of 0.1dB (sceptical).

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown
Sent: 02 April 2021 11:39
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

Mike,

 

I see 5 to 6dB. I can’t put 18v into my LNB for vertical polarisation, that’ll be the main problem.

 

I can probably squeeze 1 dB more out of my system, I may do that if I ever have time.

 

What’s the NF for a LNB? I’m using the Single Opticum LSP-02G.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike Willis
Sent: 02 April 2021 09:57
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] QO-100 Finally!

 

I can receive my own DATV signals sent with under 1 watt. I have a 2.4m dish, That is equivalent to 4W for a 1.2m dish so Simon will have enough EIRP. On receive the difference between a 2.4m and 1.2m dish is under a dB. This is because you are receiving the transponder noise floor and the link limited by the SNR on the uplink. A 30m dish would only be a dB better. Diminishing returns. Simon's dish is in between these so should be getting around 11 dB MER on the DATV beacon. There are various reasons this might not happen, dosh pointing and focus being two but phase noise being a third. Knowing what he has I would think the dish might not be totally optimised. It is easy to tell, measure the noise floor of the narrow band transponder relative to the band just below, there should be an uplift. for me it is nearly 10 dB. for a 1.2m dish it should be more than 4 dB, for Simon perhaps 6 dB.


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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


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Mike Willis
 

Hi Simon

Why can't you put 18V into your LNB? Lack of 18V PSU? You must have a bias-T as you can put 12V in. The Winterhill project includes the LNB supply so that's an option but you have to build it and I know you don't do that. How about acquiring something like this perhaps

https://cpc.farnell.com/vision/v5-033/dc-injector-3-way-tap/dp/AP02679?mckv=s93PuUNzw_dc|pcrid|224680055011|kword||match||plid||slid||product|AP02679|pgrid|51011277550|ptaid|pla-805426656427|&CMP=KNC-GUK-CPC-SHOPPING&s_kwcid=AL!5616!3!224680055011!!!network}!805426656427!&gclid=CjwKCAjwpKCDBhBPEiwAFgBzjzf0VE18-5Ks9DkD09G-4upPx_zbk2yMzhAkmhZ0TRFzUFQ2b9pFKBoCqKwQAvD_BwE

and an 18V wall wart to go with it?

Mike