Receiver/grabber improvements on VLF

Just received a special build of Spectran from Alberto I2PHD that keeps the same filename for captured grabber images. This means I can now use Spectran with my VLF grabber. This is fired up from time to time when people are doing VLF tests. It will also allow me to look for my own signal at home when I am out transmitting in the Fens locally some kms from home. I find Spectran easier to use than Spectrum Lab, which is a clever program but complicated for someone like me to configure.

I have also rebuilt the 4-5W beacon TX on 8.76kHz and given it a 1 hour continuous soak test. There is a video about this on my YouTube channel.

My next job is to work on a permanent VLF E-field probe outdoors and to make improvements to the receiving system for field use. I need a better preamp/filter that can also be used with earth electrode receiving antennas as well as the loop and E-field whips.

Looking for G3XIZ on VLF this evening

G3XIZ is transmitting with 20W to his Marconi vertical on 8.9719kHz this evening from 2000-2200z. I am looking out for his signal with my loop into both Spectrum Lab and Spectran software. You can look on my VLF grabber to see if he is visible at all over here in JO02dg. At the moment all that is visible is a wobbly 50Hz related signal and my 8.760kHz QRSS3 beacon running on a dummy load. UPDATE: nothing copied and Chris had to close because of an antenna fault at 2100z.

VLF Grabber operational capturing 8-9kHz in JO02dg

I'm setting up a VLF grabber at my home QTH to take periodic screenshots of the 8-9kHz Dreamers Band and make these available online. At the moment it is taking input from my earth electrode "antenna" into Spectrum Lab and is very much a work in progress and needs a lot of improvements on the RX and antenna front. It won't be ON unless I'm in the shack and don't need the PC for other VLF stuff.  

The resulting screen grab every few minutes appears at https://dl.dropbox.com/u/15047843/xbm_grab.jpg . 

VLF Grabber

Today I intend to make a VLF grabber to receive sub9kHz signals and automatically upload the screen grabs to the Internet. My aim is to use Dropbox as the place where the grabs will we stored and visible.

6 Spanish stations get access to 501-504kHz

The Spanish authorities have granted limited access to 501-504kHz (100Hz bandwidth, 5W) to 6 stations (EA1AY,  EA2HB,  EA3CC,  EA3WX,   EA4BVZ, and  EA5DY) until the end of May 2011,

iPod Touch 4g

Recently I upgraded my pocket PC - I used a Dell Axim for 7 years - to a new iPod Touch 4g purchased at a good price from Amazon. It really is an amazing piece of kit in a tiny size with an incredibly pin-sharp screen which is so good that individual pixels cannot be seen: the resolution is better than my TV. I've already downloaded the Echolink app (free) so I now also have a 2.3GHz pocket ham transceiver too. I hope to use it for some other ham radio applications including datamodes and VLF reception.

If you want to see what is inside the iPod Touch 4g look here for a tear-down analysis: there is a lot in this small package!

First Norwegian VLF amateur transmission

From Jan LA3EQ:

"First succesfull transmission on 8.760kHz using WSPR mode in Norway using 40 meter longwire and only speaker output from the pc soundboard as a transmitter and a 12volt to 220v transformer as impeadence "antenna matching" transformer..  Several WSPR spots of -2dB to -7 dB. distaince only 50 meters, but it is a start. Next try will be with earth dipole and 10 watts and an active e-probe antenna on receive."

VLF kite transmission by DF6NM

DF6NM's signal in the UK

Marcus DF6NM carried out another successful VLF test yesterday on 8.97kHz (200uW ERP) and 6.47kHz (50uW ERP) with reception by Paul Nicolson in Todmorden UK.  Marcus is the second German VLF amateur to be copied at this distance.

Inactive week radiowise

This week I've been very inactive on the radio because we have had our grandson's 3rd birthday party here with his French grandparents (neither of whom speak English) staying along with his mum and dad. Still, a lovely time was had and he got lots of nice presents. By the way, he now knows the difference between square waves and sine waves and loves going "oo oo", which means fiddling with the audio oscillator and scope.

Looking for G3XIZ on 8.9719kHz VLF

Looking for G3XIZ on 8.9719kHz - maybe a faint trace??

Between 2000 and 2200z this evening G3XIZ has been transmitting on 8.9719kHz VLF with his Marconi vertical and about 20W RF into it. I've been monitoring with my earth electrode antenna, a preamp/filter and a PC running Spectran on 0.17Hz resolution, but don't think I've seen any sign of him.