Tuesday 29 May 2012

Update Balun BU-50.

I now have my balun attached to the antenna, and the difference? Wow! Amazing. I can now tune to the 10m Ham band with no problems.

It makes a HUGE difference and hopefully, this will enhance my listening pleasure without the interference and other related crap associated with having an unmatched antenna.

Diamond Antenna Balun.BU-50

It has been a while since I have posted. Real life and other things getting in the way. Ok, to the purpose of this particular blog post. It is time that my HF antenna had some very much needed maintenance. In today's process of doing some much needed work, I will be adding a balun to the antenna to both improve performance of the antenna, and make some attempt to correctly match a random piece of wire to my receiver. The Diamond Antenna BU-50 balun boasts of being one of the best baluns on the market, but we shall see. The specs for such a thing are as follows.

Frequency:1.7Mhz - 40 Mhz
Impedence:50 Ohms
VSWR Less than: 1.5:1
Max Power:1.2 Kwatts

In all fairness, I am only using this balun for a reception antenna so the Max Power rating is irrelevant, but good to know when I finally get my HAM license and want to broadcast using a wire.

Wednesday 10 August 2011

Live SSTV Stream

I have built a webpage to display the latest SSTV images I have received. Please visit the following link.

Click here

The page format will be changing on a regular basis while I play with styles and formats so keep checking back to see its progression.

However, to initially set up the web page and other stuff, can be a bit cumbersome. The FTP Widget that uploads the images automatically in my view is sadly lacking and I will endevour to create a new widget that will also eliminate the need to create a template web-page for the live stream, add useful functionality and have the widget actually generate the HTML page for you, based on configurable options in the settings.

When I have successfully created the new app, I will send it to the origional author of the SSTV FTP widget for a review ( sorry John. Didn't want to steal your thunder ). I will also make it available for download with usage instructions when I am done. Watch this space.

Saturday 30 July 2011

Portal/Portal 2, SSTV images

I am sure many of you have heard of the game Portal, well, heres the thing. In the game, there are SSTV audio clips, so looking on YouTube last night, I went searching for the portal SSTV audio, and decided to decode the SSTV images using MMSSTV.





Thursday 28 July 2011

Slow Scan Television. ( SSTV )

SSTV, or slow scan television, is a way of sending images over radio. The image coded as an audio signal, transmitted, and then software at the receiving end decodes the audio back into an image. Neat huh?

This evening, listening on 14.230 Mhz I managed to receive some SSTV images. The software I use is a free app called MMSSTV. Just type that into google and you will get many links to the software. Like receiving wefax images, connect the radio to the PC and MMSSTV should automatically receive the images when any are broadcast.

Here area few I received.







Monday 25 July 2011

Antenna Overhaul

I decided today was the day I ordered new coax, connectors and other essentials for my antenna, which includes 100 meters of RG58 cable, 2 x phono plugs and 2 x phono sockets ( yup, my radio has phono socket as arial socket ) and 14SWG Tinned Copper wire ( to extend my antenna ).

I think at this point, the radio noise and interference is going to be a problem with an extended antenna, so my next project is to build an ATU specifically for the HF bands. More to come on the design and construction of that later.

Sunday 24 July 2011

Internet RTTY

I find it amazing that such an old technology like radio teletype, would find a place on the internet.

The following link is to one such place, where you can get an RTTY feed over the intermet, and you decode it like normal RTTY using RTTY software such as SeaTTY, TrueTTY just to name a few

Internet RTTY

It is interesting, and also offers you the opportunity of adding to the RTTY feed.

Enjoy :)

Saturday 23 July 2011

and of course, Malamutes...

I don't feel this page is complete, without a pic of my malamute, also one of my favorite breeds of dog.

That is Alaska, being her usual over-bearing and attention seeking self, Mitz in the corner, and me, being squashed under the weight of a dopey-mute.

Not a breed for everyone, since they shed a lot of hair, most of the time, need a lot of exercise and not known for their obedience 100% of the time. When you have a stubborn, strong willed and pig headed breed like this, it pays to be more stubborn, strong willed and pig headed than they are.

WEFAX ( Again )

I think I should talk a little more about Wefax. What is Wefax you ask?  Wefax, or sat fax or HF Radio Fax is basically a Fax weather image provided via satellite and radio for shipping and marine purposes.

All you need, is one short wave receiver capable of SideBand reception, or a standard AM set with either a built in BFO ( Beat Frequency Oscilator ) or and improvised 'BFO'. Best way to inprovise a BFO is the use of a second AM radio, held close to the AM receiver that you will be receiving on. The second AM's sets IF basically 'interferes' with your receiving set, one of the unintended side effects of this interference is, it injects a 'carrier' wave into the IF of the receiving set, thus making it capable of receiving SideBand signals. You will also need an appropriate antenna ( I use a 90 foot wire antenna strung between two trees, insulated at either end ) and of course a computer, running either Wxsat, SeaTTY, RadioComm, multiPSK or any other software capabe of decoding a FA signal.

You connect the audio output of the Radio to the line-in or mic in on the computers soundcard and adjust the recording levels accordingly making sure you dont overload the soundcard with too much audio. Next, tune your receiver to one of these frequencies..

4610 Khz ( Joint Opertions for Meteriological and Oceanic Center, Northwood UK)
7880 Khz ( DeutcherWetterDeinst, Hamburg Germany )
9110 Khz (NOAA, Boston, Massachussettes )

I list these because generally, in Europe these are usually the strongest of Wefax signals, so should be fairly easy to receive. Please note that if you have a receiver capable of sideband, then switch it to USB, and have the set frequency approx 1.9Khz below the listed frequency. This may vary from radio to radio so you will need to experiment ( for example, on my receiver, I have to tune to approx 2.5Khz below the listed Frequency.)

You should hear an audible tone, that sounds not unlike a fax, or data modem signal, well, set your software to 'start' and voila! ( with VxSat, you will need to select FM120 in order to decode the images properly. )

Here are some images that I have received using my modest setup.

This image was recevied from the Northwood Station.



Received from DwD, Hamburg, Germany..







And a Satellite IR image received from NOAA in Boston Massachusettes.

Enjoy, and happy decoding :)

New to Blogspot

I never really considered keeping a blog until now. I think my primary reason for doing so, is my hobby of radio and electronics, and the pleasure of experimenting. I felt I needed somewhere to gather my thoughts, my ideas and experimenting so I can keep it all together, to provide a digital record and most importantly, to offer something of interest to all those interested in radio, its origins and the many fun things you can still do with it today.


I am mainly interested in short wave radio and making sense of the data modes, like WEFAX, FSK just to name a few. WEFAX however, seems to have combined my obsession of the weather, and radio into one very neat interesting package :)


Anyway, thats the introduction to my blog, for what its worth and I want to see if I can make this as informative and interesting as I can make it. Enjoy :)