My Little Radio Project

[DBK]

I mentioned on another thread I was going to make a small radio I could use for sending and receiving morse code.

The following is offered not so much as a suggestion that everyone should be doing this. I would much rather be posting about trips made this year. But apart from a few breaks, these haven't happened. So as a bit of lockdown light relief here is my alternative to posting about overseas sunshine.

This was the thread :

Broken Link Removed

The idea is to make a portable system I can carry up to the top of (low ) hills with the aim of reaching distant operators. Even though the radio I'm building only produces a maximum power of just 5W (think dim torch) it could in theory contact folk in North America.

If I can get it to work and learn Morse code of course!

The kit comes from a British(?) bloke based in Turkey - married to a local I think. With the optional case and shipping it was was a very reasonable £85. The electronics on their own are about £45 ex-shipping

The radio comes as a kit with only a few surface mounted components already fitted on the board. The rest of the bits come loose in a plastic bag.

So the first step was to identify and separate everything. The extremely well written instructions include a parts list which I printed off and then cut out each line and put one in each compartment of the three cheap trays I bought. You can see the strips of paper in the photo below.

But before I got to this stage I needed some improvements to my radio shack.

The resistors in the kit are tiny and even with a magnifying glass I struggled to identify them from their coloured bands. Purples and blues were particularly hard to differentiate and the problem wasn't only my failing eyesight - it was the quality of the lighting.

So another unexpected cost was installing three 8W LED lights above the bench. These are a daylight temperature and the colours of the bands really stand out.

So with no excuses left to put it off any longer I set to work.

The thing above is described in the instructions as probably the most difficult part to make and fit. It's a toroid with four different windings. The number of turns in each winding depends on the band (frequency) you are building the set for. I didn't find the winding too difficult but wrestling the resultant octopus and fixing it to the board was interesting.

The capicitors are fitted next.

There's a lot of them.

After several more coffees and cups of tea...

There is another board which holds the controls and LCD display. Here shown fitted and within the enclosure.

And does it work?

Sort of.

I can receive CW (Morse) transmissions but it isn't transmitting. I can hear the dots and dashes I'm trying to send in my headphones but it isn't transmitting.

 

[Chris]

Don’t take this the wrong way, but you are a geek aren’t you?

I love your threads by the way.

 

[David and Sally]

Must watch this build. Love electronics but know diddly-squat about how it all works.

 

[Lenny HB]

You do like to torture yourself, sounds fun but I can't be bothered these days.
A Couple of baked bean cans and some string would have done.

 

[cbrookson]

If it works we can have a QSO- but my CW is a bit rusty. Long time since I did the test at North Foreland radio station!
73s

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[DBK]

The radio has a decoder which can translate morse code although I've discovered it only works reliably if everything is perfect. In the shot below you can see "N8BJM" which is the callsign of someone on the West Coast of the US - but the question mark after it suggests this is part of a conversation along the lines of asking about N8BJM especially as I think it is preceeded by what might be a garbled callsign also followed by a question mark.

There is a comprehensive fault finding guide available which I will start working through tomorrow. It might just be a dry joint or even a non-joint somewhere.

Covid will keep me home long enough to sort it I fear.

 

[Tombola]

The radio has decoder which can translate morse code although I've discovered it only works reliably if everything is perfect. In the shot below you can see "N8BJM" which is the callsign of someone on the West Coast of the US - but the question mark after it suggests this is part of a conversation along the lines of asking about N8BJM especially as I think it is preceeded by what might be a garbled callsign also followed by a question mark.


View attachment 448699

There is a comprehensive fault finding guide available which I will start working through tomorrow. It might just be a dry joint or even a non-joint somewhere.

Covid will keep me home long enough to sort it I fear.

Thats Donald J Trump sos

Well done you, I wish I had the patience

 

[Gromett]

That brings back many good memories. In the early 80's I took the RAE exam as soon as I turned 13 which was the age limit back then from memory.
Then my whole family got into it with every member getting their B license and 2 of them their A license.

My school CDT project was a self designed Dual Conversion superheterodyne receiver using dual gate fet design. I couldn't do it today as I am so out of practice and have forgotten most of that stuff. I do remember cutting my thumb quite badly on the fins of the big variable capacitor though.

I then got into packet radio which was more my cup of tea so dumped the morse lessons and starting hanging out with a guy doing slow scan TV and moon bounce stuff. He was an old boy who built quite often using no vero board, pcb or tags. Everything was built using just the wires of the components. He got some real birds nest stuff going. His packet modem though was a thing of beauty.

Thanks for these posts. You have brought back some extremely fond memories, and a bit of a desire to get back into it.

 

[Wildbill]

.-- . .-.. .-.. / -.. --- -. . / - .... .- - / -- .- -.

-... .. .-.. .-..

 

[DBK]

Don’t take this the wrong way, but you are a geek aren’t you?

I love your threads by the way.

Must watch this build. Love electronics but know diddly-squat about how it all works.

I fear I am becoming a geek although I may have left it a bit late.

My understanding of electronics has improved a huge amount after studying for the ham radio exams. I've past the Foundation and should have taken the Intermediate today but had to cancel due to a family obligations I couldn't escape from. I'm retaking it next month and will try for the Full licence after that. The Full is what I need as it is the only UK licence you can use in mainland Europe. The Full exam has the heaviest electronics and studying this has been useful.

Electronics is like plumbing - but with more pipes, pressures and temperatures than in a domestic central heating system.

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[DBK]

That brings back many good memories. In the early 80's I took the RAE exam as soon as I turned 13 which was the age limit back then from memory.
Then my whole family got into it with every member getting their B license and 2 of them their A license.

My school CDT project was a self designed Dual Conversion superheterodyne receiver using dual gate fet design. I couldn't do it today as I am so out of practice and have forgotten most of that stuff. I do remember cutting my thumb quite badly on the fins of the big variable capacitor though.

I then got into packet radio which was more my cup of tea so dumped the morse lessons and starting hanging out with a guy doing slow scan TV and moon bounce stuff. He was an old boy who built quite often using no vero board, pcb or tags. Everything was built using just the wires of the components. He got some real birds nest stuff going. His packet modem though was a thing of beauty.

Thanks for these posts. You have brought back some extremely fond memories, and a bit of a desire to get back into it.

The data modes are very interesting. CW is probably the best for range with purely human involvement but data modes can go much further - one system from memory can take ten seconds to send a single "dash" and short messages can take ten minutes to transmit.

As I understand it the concept is a bit like stacking multiple exposures of the night sky. If you take enough you can compare each shot and look for what is common in each. The rest is noise and can be discarded.

The data modes do something similar. If you listen long enough they can filter out the noise even when the signal is otherwise completely lost in the background.

 

[Ridgeway]

Nice thread and great topic

In trying to educate the young ones i recently explained about morse code and how it was used, No2 daughter quickly mentioned the Titanic and said "wasn't it morse code that they used to send out a signal" of course i replied yes and that they used an SOS signal, arh No 4 daughter said, i've heard of that, isn't that "Save our Selves"

I think we all learned something that day.

My 89 year old father is still tuning in most evenings on his SW radio (with a mast i erected some 20yrs ago).

 

[DBK]

If it works we can have a QSO- but my CW is a bit rusty. Long time since I did the test at North Foreland radio station!
73s

If I can get it work a slow QSO would be perfect. QRS or better still QRSS.

 

[John Barrett]

Nice thread and great topic

SNIP

My 89 year old father is still tuning in most evenings on his SW radio (with a mast i erected some 20yrs ago).

I didn't know that Short Wave listening was still available.
Many years ago I bought myself one of these as I was travelling the world. It was a fabulous little radio. Somebody nicked it...
<Broken link removed>

 

[cbrookson]

I've had great fun this year using FT8 data mode. It has the advantage that you can run low power and modest antennas and still work the world. If you have a licence then it's worth having a go. Great fun for computer and radio geeks as it combines both, it's designed by Joe Taylor who has a Nobel prize for his work on Pulsars.

During lock down FT8 has been great, as I can have a boring Zoom call in one window on my PC - and talking to the world on the other one (and I can be seen looking interested at the screen!).

There is still active Short Wave Listening going on - the British DX Club for example is a good Club to join up ....

Sorry if this is double-dutch to some!

Cheers

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[Spriddler]

Oh, my! The patience needed. Great project. I even drink coffee as I can't hang around waiting for a tea bag to brew.

Two thoughts came to mind.

1. Do you Tx/Rx using a horizontal or vertical aerial? How large is it?

2. Incredible that a 5w transmitter can in theory reach N America.

It's not really the same science but bearing in mind the discussions on here about voltage drop in a couple of metres of m/h wiring I find it surprising that the 6,000km transatlantic telegraph cable was effective bearing in mind the puny Leclanché celled batteries available in 1858.

Have you given up hope on hearing from your wayward balloon?

 

[34127]

Great post to read, spent many a happy hour in my more youthful day messing around with a bit of veroboard and a few components. As I started my work in electronics and specialising in medical electronic engineering I lost the opportunity to do much practical work on pcb fault finding and product modification/improvement because of all the protocols I had to follow and approvals needed for any changes to original design spec.

 

[autorouter]

even with a magnifying glass

I use a pair of very strong reading glasses (+3.5) instead of a magnifying glass. Hands-free, and binocular vision too. You have to move the work or your head so they are much closer than usual. Good for things like fine soldering, where you don't have a spare hand to hold the magnifying glass. A head torch is useful too.

 

[Ingwe]

I've been interested in valve amplifiers for 30 years and have contemplated building my own. Regrettably, though now retired, we have no where suitable in our house for such a build. A couple of years ago, I met another valve devotee who had access to a perfect lab, complete with oscilloscopes for testing, but he got ill and is now not responding to emails (the only way I had of contacting him) so am fearing the worst.
Still, I have the BBC manual on valve amplification, written in the 1930s and I find reading this satiates my interest. Do you think I'm too late for help?

 

[John Barrett]

I've been interested in valve amplifiers for 30 years and have contemplated building my own. Regrettably, though now retired, we have no where suitable in our house for such a build. A couple of years ago, I met another valve devotee who had access to a perfect lab, complete with oscilloscopes for testing, but he got ill and is now not responding to emails (the only way I had of contacting him) so am fearing the worst.
Still, I have the BBC manual on valve amplification, written in the 1930s and I find reading this satiates my interest. Do you think I'm too late for help?

My interest in valve amps evaporated when the big capacitor in my hifi amp behind the settee exploded! It rained confetti on everything and my then wife was not best pleased...

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[DBK]

Do you Tx/Rx using a horizontal or vertical aerial? How large is it?


Have you given up hope on hearing from your wayward balloon?

The antenna is just a bit of wire 10m long strung in the garden. It is horizontal but for HF the orientation doesn't matter, unlike the higher frequencies. I've got a 5m fibreglass pole I'm going to use to raise it on mountain tops - if I can get it to work of course. The will create an inverted L shape which combines a bit of both vertical and horizontal wire.

 

[eddie]

A bit behind the times you lot!

I made a Morse code "lamp" with a peg, battery and cycle light following the detailed technical instructions in my copy of the iSpy book of "Spies"

I was eight! and my signals could be read from hundreds of millimetres!

 

[John Barrett]

The antenna is just a bit of wire 10m long strung in the garden. It is horizontal but for HF the orientation doesn't matter, unlike the higher frequencies. I've got a 5m fibreglass pole I'm going to use to raise it on mountain tops - if I can get it to work of course. The will create an inverted L shape which combines a bit of both vertical and horizontal wire.

I still have my 5m long wire antenna as supplied with the ICF1600. Worked a treat in some backwoods hotel in North Pakistan!

 

[Zoobec]

Must watch this build. Love electronics but know diddly-squat about how it all works.

Me too OH would understand it all, but not me!

 

[DBK]

This is an embarrassing update - the radio seems to be working and probably has been since I finished building it.

The problem was the cheap radio I was using to pick up the transmitted signal. It was a £30 USB radio (known as an SDR) which plugs into my PC. I know the one I have doesn't work well at lower frequencies but you need to spend around £150 or more to get one which does so I just made do with the cheapie version. Despite being virtually next door to my new home-built radio it wasn't registering so much as a flicker of any signal.

Then I remembered I had a thing called an upconverter which adds 125MHz to the received signal to bring it into the range the SDR radio works best at.

And this was the result:

The little stream of dots running vertically up the lower part of the screen are the signal - what they say is CQ CQ DE M7WIV which in Morse code operator-speak is "any station from M7WIV" - which is my callsign. The signal in this screenshot is very weak as the radio was connected to a dummy load rather than a proper antenna but enough signal escaped from the dummy load for the SDR to pick it up. When I connected the proper antenna stretched over the garden the signal was much stronger.

What I haven't been able to do is any sort of range test but I'll see if I can find someone to listen out for me. I've heard a few signals this afternoon but so far I haven't managed to get anyone to bite - they probably recognise my ham-fisted transmissions and are ignoring me - or equally likely they aren't hearing me at all and I still have a problem.

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[DBK]

I've just learned of a thing called the Reverse Beacon Network which I can use to see how far, if anywhere, my signals are going. I'll give it a go tomorrow.

RBN - Reverse Beacon Network

beta.reversebeacon.net

 

[DBK]

And today's good news is (roll of drums please)

Using the Reverse Beacon Network I've been "spotted" in Iceland, Finland and Italy! It doesn't know my location other than I'm in England but the spotters locations must be more exact.

I'm very chuffed.

 

[Ingwe]

I can imagine how chuffed you feel.
I used to think how wonderful it must have felt to have invented the telephone and then realising that you didn't have anyone you could ring!

 

[DBK]

I can imagine how chuffed you feel.
I used to think how wonderful it must have felt to have invented the telephone and then realising that you didn't have anyone you could ring!

I'm redoubled my efforts to learn morse code as a consequence of this result! It's as if I've got a telephone and there are people to ring - but I have removed the earpiece off my set and I can't understand any replies.

 

[DBK]

Been picked up by someone in Russia now! I'm hoping later today, when daylight arrives there I might reach North America - but that is probably a bit optimistic.

EDIT Spoken out of turn - just been spotted from Canada! My first trans-Atlantic message and not bad for what is probably, given the voltage I'm running it on only 4W of power at most.

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