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SAQ VLF transmission on Christmas Eve


Chris Moulding
 

Each Christmas Eve the SAQ VLF transmitter in Sweden sends out Christmas greetings on 17.2 kHz.

I've been setting up a VLF/HF Loop Antenna Amplifier with a bicycle wheel rim loop getting ready to receive the transmission.

The output from the Loop Antenna Amplifier is high enough to directly drive a computer sound card so with a bit of software you don't need an exotic VLF receiver to hear the transmissions, just a BNC male to 3.5 mm jack cable to the audio in socket. I recommend that you follow the modification in the recent Service Bulletin 3 and add a 1000 uF capacitor to the 5V input for best results.

The software I'm using with a Windows laptop is SAQrx ver 0.98 by Johan Bodin, SM6LKM. Here's a link to it:

http://www.crosscountrywireless.net/SAQrx_0-98.zip

More details on the SAQ transmitter and the Christmas Eve transmission at the following link:

https://alexander.n.se/scheduled-transmission-from-grimeton-radio-saq-on-christmas-eve-december-24-2018-2/?lang=en

This is what you should see when it's working. You can slide the yellow box around to hear different stations and click on Tune SAQ to tune to 17.2 kHz.



Happy Christmas!

Regards,

Chris


Chris Moulding
 

I copied the Christmas message from SAQ at 10 dB above the background noise floor here in north west England.

Very nice CW from the last Alexanderson alternator transmitter.

I was using the bicycle wheel rim loop with the VLF/HF Loop Antenna Amplifier straight into the PC sound card.

Regards,

Chris


David Cutter
 

Hi Chris

Can you put the audio onto your web site so we can hear for ourselves?

David G3UNA

On 24 December 2019 at 11:11 Chris Moulding <chrism@...> wrote:

I copied the Christmas message from SAQ at 10 dB above the background noise floor here in north west England.

Very nice CW from the last Alexanderson alternator transmitter.

I was using the bicycle wheel rim loop with the VLF/HF Loop Antenna Amplifier straight into the PC sound card.

Regards,

Chris


Tim Hague M0AFJ
 

If anyone wants a recording PM me

Best Regards
Tim Hague


On 24 Dec 2019, at 12:32, David Cutter via Groups.Io <d.cutter@...> wrote:



Hi Chris

Can you put the audio onto your web site so we can hear for ourselves?

David G3UNA

On 24 December 2019 at 11:11 Chris Moulding <chrism@...> wrote:

I copied the Christmas message from SAQ at 10 dB above the background noise floor here in north west England.

Very nice CW from the last Alexanderson alternator transmitter.

I was using the bicycle wheel rim loop with the VLF/HF Loop Antenna Amplifier straight into the PC sound card.

Regards,

Chris


Chris Moulding
 

I covered the full 20m CW transmission so it's about 20 minutes long.

The Christmas message begins at 14.40 minutes into the recording.

Here's the link to my recording:

http://www.crosscountrywireless.net/SAQ_at_G4HYG_24_12_2019.mp3

Regards,

Chris


Stephen Farthing
 

Hi All, 

In the past I’ve received this, with some difficulty, using a few meters of wire plugged into a sound card. I’m sure the loop is a better solution though.

Regards, 

Steve G0XAR 


On Tue, 24 Dec 2019 at 13:01, Chris Moulding <chrism@...> wrote:
I covered the full 20m CW transmission so it's about 20 minutes long.

The Christmas message begins at 14.40 minutes into the recording.

Here's the link to my recording:

http://www.crosscountrywireless.net/SAQ_at_G4HYG_24_12_2019.mp3

Regards,

Chris


stephen_qrp@...
 

Hi Chris

Out of curiosity what size bicycle wheel rim do you use ? I am thinking wheel diameter amd rim width, also assume aluminium not steel.
Good luck

Stephen
M0GWI


Oene Spoelstra
 

I use an alu bar of 2 meters and bended into a loop.  30 mm x 2 mm.  Works fine! 

Op di 24 dec. 2019 17:38 schreef stephen_qrp via Groups.Io <stephen_qrp=yahoo.com@groups.io>:

Hi Chris

Out of curiosity what size bicycle wheel rim do you use ? I am thinking wheel diameter amd rim width, also assume aluminium not steel.
Good luck

Stephen
M0GWI


Arlene Channell <arlene.channell@...>
 

Merry Christmas and a blessed New Year!


-----Original Message-----
From: Chris Moulding <chrism@...>
To: CrossCountryWireless <CrossCountryWireless@groups.io>
Sent: Tue, Dec 24, 2019 9:31 pm
Subject: Re: [CrossCountryWireless] SAQ VLF transmission on Christmas Eve

I copied the Christmas message from SAQ at 10 dB above the background noise floor here in north west England.

Very nice CW from the last Alexanderson alternator transmitter.

I was using the bicycle wheel rim loop with the VLF/HF Loop Antenna Amplifier straight into the PC sound card.

Regards,

Chris


Chris Moulding
 

I use a 700C alloy bicycle wheel rim. It's 622 mm diameter. From memory it's 22 mm wide.

Regards,

Chris


stephen_qrp@...
 

Thank you Oene

I have a loop with exactly the same dimensions. I have found the size to cause overloading and a very high noise floor.
I will now try the bycle wheel size used by Chris

Kind regards

Stephen


stephen_qrp@...
 

Thanks Chris, going to give the bike wheel a try.

Regards

Stephen