Differences

This shows you the differences between two versions of the page.

--- dwd-wefax [2022/02/24 15:39] – mm3iig
+++ dwd-wefax [2022/02/24 17:13] – mm3iig
@@ Line 1: / Line 1: @@
 ====== DWD (Deutscher Wetterdienst) Weather Fax - 24th Feb 2022 ======
-The following images are a collection of images decoded from the DWD station DDK3 Hamburg (7880 kHz centre frequency) on the 24th February 2022. Below this are some notes on software/hardware used for this decoding. Images have been rotated if required before uploading.
+The following images are a collection of images decoded from the DWD station DDK3 Hamburg (7880 kHz centre frequency) on the 24th February 2022. Before the images are some notes on software/hardware used for this decoding. Images have been rotated if required before uploading. As the day went on the band seemed to get more noisier, meaning certain charts are somewhat blurry. There may also be some multipath shenanigans going on as well.
 Captures by Mark 2M0IIG, QTH Edinburgh
@@ Line 7: / Line 7: @@
 The schedule for the DWD fax service can be found here: https://www.dwd.de/EN/specialusers/shipping/broadcast_en/broadcast_fax_112016.pdf?__blob=publicationFile&v=1
+A full list of worldwide Wefax services provided by the US National Weather Service can be found here: https://www.weather.gov/media/marine/rfax.pdf
+===== Hardware/Software Setup =====
+==== Hardware ====
+Radio used was an [[https://www.sdrplay.com/rsp1a/|SDRplay RSP1A]] (around £99 in the UK). The antenna was a [[https://qrpguys.com/qrpguys-40m-10m-ununtenna|QRPGuys 9:1 UnUntenna]] with around 10 metres of wire attached and a counterpoise (usually used for transmitting). The antenna wire is trapped by a window, and then goes to a pole outside, height is 4 metres. This is fed with around 5 metres of RG58 coax, and there are clip-on ferrites (cheap ones from Amazon, by no means an ideal setup) used to choke off the common mode current - again, this is more important when transmitting with it, really.
+The SDR is connected to a standard Windows 10 laptop (HP Pavillion).
+==== Software ====
+I am using [[https://github.com/AlexandreRouma/SDRPlusPlus|SDR++]] to drive the RSP1A. The audio output is routed through [[https://vb-audio.com/Voicemeeter/|Voicemeeter]], a virtual audio cable application. [[http://www.w1hkj.com/|FLDigi]] is used for decoding the signal after it exits the virtual audio cable.
+I have adjusted the settings for the Wefax decoder in FLDigi to make sure that it auto-starts, has automatic frequency control turned on, and I have adjusted the shift to make sure it matches the expected +/- 425 Hz for the black/white tones.
+Also note that when tuning in USB mode you should tune 1.9 kHz lower than the specified frequency to obtain the entire signal in the passband. For DDK3 this means a frequency in SDR++ of 7878.1 kHz.
 ===== Decoded Charts =====
@@ Line 61: / Line 78: @@
 Northwest Atlantic (Canadian Ice Service), from 0000 UTC
+{{:wefax_20220224_151926_7878100_ok.png?direct&600|}}
 Baltic Sea, from 0900 UTC
+{{:wefax_20220224_154037_7878100_phasing.png?direct&600|}}
 European Arctic Sea, from 0900 UTC
+{{:wefax_20220224_155645_7878100_nocorr.png?direct&600|}}
 ==== Wave Prediction Charts ====
@@ Line 71: / Line 94: @@
 {{:wefax_20220224_104913_7878100_ok.png?direct&600|}}
-===== Hardware/Software Setup =====
-==== Hardware ====
-Radio used was an [[https://www.sdrplay.com/rsp1a/|SDRplay RSP1A]] (around £99 in the UK). The antenna was a [[https://qrpguys.com/qrpguys-40m-10m-ununtenna|QRPGuys 9:1 UnUntenna]] with around 10 metres of wire attached and a counterpoise (usually used for transmitting). The antenna wire is trapped by a window, and then goes to a pole outside, height is 4 metres. This is fed with around 5 metres of RG58 coax, and there are clip-on ferrites (cheap ones from Amazon, by no means an ideal setup) used to choke off the common mode current - again, this is more important when transmitting with it, really.
-The SDR is connected to a standard Windows 10 laptop (HP Pavillion).
-==== Software ====
-I am using [[https://github.com/AlexandreRouma/SDRPlusPlus|SDR++]] to drive the RSP1A. The audio output is routed through [[https://vb-audio.com/Voicemeeter/|Voicemeeter]], a virtual audio cable application. [[http://www.w1hkj.com/|FLDigi]] is used for decoding the signal after it exits the virtual audio cable.
-I have adjusted the settings for the Wefax decoder in FLDigi to make sure that it auto-starts, has automatic frequency control turned on, and I have adjusted the shift to make sure it matches the expected +/- 425 Hz for the black/white tones.
-Also note that when tuning in USB mode you should tune 1.9 kHz lower than the specified frequency to obtain the entire signal in the passband. For DDK3 this means a frequency in SDR++ of 7878.1 kHz.