G3XBM grabber

Some browsers will not allow page embedding for security reasons. 

If you can see embedded pages you may be amused to look at my grabber, that is mostly on 10m FT8 RX.  If embedding does not work on your browser, there is an alternative link. 

As you can tell, 10m is pretty good now and has been in recent days.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/10m-ft8-grabber .

10m FT8 grabber

If you want to see the stations being copied here try this link. If your browser stops embedded pages try the link given instead.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/10m-ft8-grabber .

Or try https://pskreporter.info/pskmap.html?preset&callsign=g3xbm&txrx=rx&band=27999999-31000000&timerange=86400&mapCenter=16.191222112538867,36.66666666666666,2.925736525647676 which should be the direct permalink.

Just occasionally, the grabber may be looking at something else, although mostly it will be on 10m FT8.

Grabber

A reminder that my new webpages have a grabber. This is mainly on 10m FT8, although occasionally it is looking somewhere else. You can see what I am spotting.

Some browsers do not like embedding as this can pose a security risk. There are work-arounds, but if you are not sure, do not.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/10m-ft8-grabber .

10m FT8 grabber

One of the things now possible on my new web pages is embedding. This has allowed me to add a grabber, so you can see what I am doing on PSKreporter maps. I think you can change the menus. Certainly I can. At the time of writing, I am looking at the last few hours on 10m FT8 RX.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/10m-ft8-grabber .

10m FT8 Grabber

 It looks like I can do this on Google New Sites with embedding. For now, I have a temporary page.

See https://sites.google.com/view/grab10a/home .

10m FT8 grabber

Before long, I would like to add a grabber on my website to show the stations I am spotting on 10m FT8. The page is already there, but I don''t yet know how to do this! 😁

As a PC novice this has to be really, really simple.  Steve G1KQH is also after the answer.

If you know a very easy way to do this, please let me know! 

What I really want is to be able to show the PSKreporter map screen that I can see.

See https://sites.google.com/site/g3xbmqrp3/10grab .

At the moment, the grabs are being manually uploaded.

Grabber issues

For most of the day, I have been struggling to automatically save screen shots to my webpage. As of now I have not found a way. In the end I shall succeed.

Making WSJT-X screengrabs public

As mentioned yesterday, David G0LRD has a very useful feature on his QRZ.com page. If you go to the link provided you can see what 2m FT8 looks like at his QTH. I have already used this to see if my signal is OK. At the moment, I am not sure how he does this, but it looks a good feature.

Now, in the past I used Spectrum Lab to create a VLF grabber. I need to find out the best way for me, as I am definitely not a software expert!

If I can save the WSJT-X page image to Dropbox and make this public I think I can do it. I'll investigate. If not, I shall have to ask David! It would be good to be able to do this for any mode and any band that I am on.

HELP!!! Can someone please tell me how to automatically save screenshots or active windows panels to Dropbox?  I know how to do this with "prt sc" but want to do this automatically. Basically I need to do this regularly, without manual intervention, whenever WSJT-X is on.

Worldwide 136/137kHz grabbers + a simple 2200m RX (kit or ready built)

This link to a very useful list of 2200m grabbers worldwide was found on the website of Yuki JA5FP.   If you are interested in 136/137kHz this list of grabbers may be very useful.  A grabber is a receiver that uploads what it receives to the internet, usually as a spectrograph.

For how to make your own grabber, see how I did it. My grabber is usually only active when I do experiments. See https://sites.google.com/site/sub9khz/vlf-grabbers/vlf-grabber-creation . I used a public folder in Dropbox and pointed my grabber website to this location. In my case I was monitoring 8.97kHz VLF,  or thereabouts, but the same idea will work at any frequency. I used Spectrum Lab or Spectran software to do the actual "grabbing". Other methods are equally valid.

Also on Yuri's site are details of his 136/137kHz receiver. See http://icas.to/lineup/idc-136ii-kit-eng.htm .  This simple, but very effective, receiver uses a divided down HF crystal to give a very stable LO frequency of 130kHz. The output feeds a PC using Spectrum Lab or Spectran software. The receiver is available as a kit or ready built. Ready built the cost (with enclosure and shipped to Europe) is currently $110.  I have no idea if duty is payable.  Kits (less enclosure) is $75 shipped to Europe.

G3XBM online grabber

This evening I've been setting up my on-line grabber again so that I can monitor VLF, LF or MF activity and upload what I am receiving to the internet for others to see. The grabber is, at this stage, only on intermittently as I experiment. The plan is to have a dedicated VLF or LF receiver and PC for this purpose, so the grabber can be run almost 24/7.

The main weak signal detection is done using Argo software running on my PC connected from my RX via the SignaLink USB interface. The captured signal is then uploaded to a location in my public Dropbox which is then linked to from my webpage. So, what appears on the G3XBM online grabber page is what I am seeing with Argo. The direct link to the Dropbox image is http://dl.dropbox.com/u/15047843/g3xbm.gif .

G3XBM online grabber

VLF amateur activity

There is a new VLF grabber at Darmstadt Germany that may be useful for 8.97kHz tests. It is at http://skmail.ikp.physik.tu-darmstadt.de/gvw/grabber.html. The grabber is primarliy there for VLF research into earthquake precursors.

Stefan DK7FC reports that the permit he has to use a 300m kite antenna expires soon, so he may try a further soon before that date.  Chris G3XIZ is still hoping to resume VLF tests once a new loading coil is wound. He is looking for a suitable (very long!) source of PVC covered wire.

136kHz grabbers and a DC receiver for the band

A list of all the known LF grabbers (on-line to the internet LF receivers) in the world is available at http://icas.to/argo/grabbers-list.htm . A receiver to use with a 136kHz grabber is available as a kit or ready built from http://icas.to/e/ . This is a simple, but effective, direct conversion design which is already in use at several grabbers around the world.

My VLF grabber on for DK7FC's tests on 8.97kHz

My frequency locked VLF grabber using Spectrum Lab software, running at QRSS600 speed (i.e. slow and narrowband),  is now active until Saturday evening in the hope I may see a trace of DK7FC's 9th VLF "kite antenna" transmission on 8.970kHz on Saturday. He will be using both QRSS and DFCW. He hopes to run up to 100mW ERP this time.

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 . 

DK7FC's 6th VLF kite TX experiment

Stefan DK7FC is testing his 600W VLF transmitter into a 200m high kite supported vertical today (Aug 1st). He expects to radiate about 10dB more than in his last test (on 8.97kHz) and may transmit at a slightly lower frequency today (around 6.5kHz) depending on where the antenna is best matched. You can check progress on his grabber at http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber2.html .  Results from his last tests were amazing with reception across Europe in DFCW600 mode (dual frequency slow CW). For a summary of the reports (screen grabs) see http://abelian.org/vlf/ss100321/.  To copy his signal you will need a decent low noise/high dynamic range receiver (E-field probe or loop with preamp and filters) at VLF feeding into a PC running a package like Spectrum Lab, Argo or Spectran using narrow 3...5 mHz FFT settings and about 1 minute per pixel running speed. You also need to know precisely where to look, so calibration will be very important.

DK7FC's 8.97kHz VLF grabber active antenna

DK7FC runs a grabber on 8.97kHz so he can monitor signals testing on this VLF frequency. He feeds the signal from this active antenna into his PC's soundcard. This is a sketch of the schematic that Stefan posted on the LF reflector today. He has since added some additional C between the drain and ground to reduce the intermod products from LW/MW broadcasters that otherwise produce a strong line on 9kHz.