Radio and rails...

M0RVB

QRP Labs CW transceiver

I finally got round to starting to build the QRP Labs CW txvr kit which I've had since the 2018 Hamfest. Well, no sense in rushing things. I mentioned before the quality of the kit and the really excellent documentation PDF. I think I'm up to page 25. The documentation is all step by step and easy to follow, with a drawing on each step showing what goes where. The one I got is for 40m - the kit comes with a low pass filter and components specific to the band you request. Of course I do still need to learn Morse! That's still on my list of things to do which includes finish the QO100 project which now has two more kits of parts to build, and read up on the full licence for when, hopefully they release the online exam. Here is a shot of the wound components which, although time consuming was actually quite fun. And finally the completed board with the LCD in place. I went through the alignment process which all went according to plan using the built-in menus. The first pic is of the board powered and aligned and the second a bit of…

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M0RVB

Wet string effect

My bit of wet string in the loft, or rather, my fan dipole has been doing quite well of late, albeit only on FT8 and FT4. By fan dipole you are no doubt thinking of a dipole made up of several, i.e. more than two, dipoles cut to various bands and all terminated on one coax. Well, yes, but I only ever got round to making it for 20m and 6m. But even there it has been doing well these past few weeks with all of Europe in easy reach and forays into USA as far as the west coast, Canada, South America, the top of Africa and the Middle East, plus occasional contacts in Turkey, Russia, Oman and Kazakhstan. Not too bad at all given the 20m wires are far from straight, being bent at the ends to fit and not straight horizontally either. I mean it's sort of an inverted vee with a level bit in the middle and does seem fairly omnidirectional, probably by accident but hey. It will tune on all bands from 40m to 6m thanks to the YT-1200. Since I passed the Intermediate I've set the FT450D to 30W, the maximum for the tuner,…

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M0RVB

MiniTioune software

So… the buck converter module arrived and I soldered it in and set the voltage to 3.8V. One of the voltages was wrong. It transpired that I had a resistor of the wrong value, not far out mind, just a few ohms… ok, 560K instead of 56K! Ahem. Right, fixed that and the voltages are all correct so the serit module got soldered in and the USB module fitted. It was now that I realised that one needs to first register on the VivaDATV forum for access before you can download the software. Yup, read everything first… Anyway, the pause allowed me time to go back to the workshop and add the resistor needed for the V0.8 and newer versions of the software. Did I mention reading everything first? I got the software today and ran the test program. This came up with two errors to do with the USRC and LAV filters and fixed by running packages that come as part of the MiniTioune ZIP. And success, all tests passed. I have a box on order but otherwise it's a matter of testing on-air now, or testing using the feed from a satellite dish. But now it's raining and…

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M0RVB

MiniTiouner hardware

Typical! I finally made time today to build up the Minitiouner hardware (https://wiki.batc.org.uk/MiniTiouner_hardware_Version_2) which had been sitting in various bags in a tray for a year now. Everything went well (the PCB is very finely made) right up to installing the step down buck regulator of which I had two from eBay. So... step down buck regulators... they were right here in the rubber component mat. Where is the rubber component mat. Yup, the workshop has been tidied up and rearranged twice since all the components arrived and for some unknown reason I put the darn buck regulators on the bench and not in the same tray as the rest of the bits. And they are now nowhere to be seen. More on order from eBay... serves me right. Edit: typical. So the new ones arrived and the unit is working. Today I found the ones I ordered previously inside the envelope that the PCB came in, clearly placed there by me so I would not lose them! I now have 5...

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M0RVB

Creed 444 progress

After ages of it sitting there taking up bench space and having been moved about the workshop 3 times I finally made time to check the output waveform from the 444 today. Seeing I have a nice new shiny 'scope what better test? Failed miserably of course... After 5 minutes reading the 'scope manual (!) I can now capture the keyboard output from the 444 and apart from a lot of ringing it appears to be generating the correct codes and spacings. No surprises on the distortion given it is switching between + and - 80V in quick succession with no form of conditioning. But, given the teleprinter refuses to print the correct letter for the pressed key it does suggest this is down to adjustment in the receiving setup and not the keyboard transmitter. Here are the characters R and Y: I also checked the output from the TDMS5BV which is creating a nice, usable stream. Here it is repeating the character R: Now, feeding the stream of characters from the TDMS5BV into the 444 and checking what it is trying to print out is somewhat enlightening. Y comes out fine, but R comes out as G and I…

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