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A real analoge radio window to Europe!
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Author:  Geek [ 17 Apr 2017, 13:27 ]
Post subject:  Re: A real analoge radio window to Europe!


I can make most of that out.

Looks like despite 11M power restrictions, you have some serious leeway in modes. On the books at least, anything more than "10-4 Good Buddy" ops here are verboten. You have packet! :D

On the ISM band plans, I like the idea of EIRP. Ours are in mV/M @30M (instead of the 3 or 10 the calculators are based on) :eek:

You've got some pretty good microwave power allowances, too.

Author:  joeberesf [ 17 Mar 2018, 16:42 ]
Post subject:  Re: A real analoge radio window to Europe!

Hello radio friends, it's going on.....
First I started with an Arduino CW decoding project and then expanded with a small CW transmitter of just 1W. It is basically an old USA amateur transmitter kit from the 1950s. I was able to receive 800km myself via Completely crazy because you can check the frequency and bandwidth visually and acoustically well. I'm totally excited and now wants to apply for the license.

Here are a few pictures links and videos of my projects and amateur researches. Please look to the last link to my basics with 6V6 tube! The basics for my EL84 transmitter.

Have fun

My Arduino CW- decoder. Mic, line in and key. 8-) tone- decoder is LM 567
NE555 tone generator for the key!
online calculator for LM567 here...


YT- Video / Decodeing from computersoftware

YT- Video / Decodeing from old russian receiver R311

CW- transmitter with EL84/ homebrew

Check with 350km!

USA Kit 1950th / Basics, please have a look!

Author:  Gio [ 22 Mar 2018, 20:40 ]
Post subject:  Re: A real analoge radio window to Europe!

Hi Joe,

Nice work on the transmitter. It must have been quite remarkable picking your broadcast up on the websdr at that distance.

Author:  joeberesf [ 23 Mar 2018, 17:32 ]
Post subject:  Re: A real analoge radio window to Europe!

Hello Gio,
thanks for your reply
yes... it is impressive to receive yourself via websdr. Because there are many websdr receivers in europe, you can explore your distance well. It is important that the bandwidth of the CW signal is very narrow. First I start with a directly conntected RF- I have used a 80m quartz .... and pull this over an additional LC combination by max +/- 2kHz. It is a Collpitz- oscillator. At 40 and 80m I installed a collinsfilter for best antenna matching. Bandwidth <100Hz. Only in this way are large distances with only 1W-2W possible.

quarz ziehen.png

Completely crazy is the use of the Arduino decoder. I have now adapted the software to set a fast relay. This relay replaces the Morse- key on the EL84- transmitter. I now see what I write with the Morse- key (TFT- display) and the relay gives the Morse code to the CW transmitter. It is also possible to write a normal text on the PC and send it to the transmitter in Morse code. This small sensitive relais swiched in maximum 25wpm. If you get an answer from websdr, you can translate it again with the decoder immediately. There is now a switch > Send and receive < at the arduino decoder for working with the computer. Now I want to build everything in a housing, the CW transmitter is shielded and I'll mount the stronger tube 6V6.


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