Archive for the ‘Uncategorized’ Category
Ultimate 3 kit build
I thought my hands and eyes were good enough to make a start on this kit, which I have only just unpacked, having had it for months. I was waiting until I was less clumsy. When built, this will make a really useful WSPR beacon.
The packing is wrong as I had asked for a GPS module, which is missing, but there is a surplus relay board in the box. I was very careful unpacking the kit. and have left in packets those parts not yet needed. Some are anti-static.
Sadly, my eyes and hands are not really good enough: I started on the 10m LPF PCB and, frankly, this was a real struggle both for my eyes and hands. Tomorrow I shall test this with my generator and 50 ohm load.
Two people have very kindly offered their help building the kit. I fear I shall have to admit defeat and ask them to help me. This is a great pity as I was so hoping I’d be fit enough to build this. Sadly, this seems unlikely any time soon. My stroke is taking its toll on my abilities. WSPR is OK, but I am struggling with building still. Talking in tonight’s contest will be hard.
Another Pixie
Yet another variation on the Pixie arrived by email today from Sverre Holm in Norway who has LM386 mods to reduce BCI, provide mute and add sidetone.
See http://la3za.blogspot.no/2003/04/using-pin-7-of-lm386-to-reduce-bci-and.html .
This looks a very useful mod to this simplest of circuits. Sverre also added a much wider tuning range that helps to get contacts. Low power does not seem to be the main handicap.
Polyakov Pixie
Peter DL3PB has sent details of his version of the Pixie transceiver. He claims no broadcast breakthrough by using this configuration and lots of QSOs.
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| Peter DL2PB’s Polyakov Pixie |
Pixie and Micro 80
These little QRP transceivers first made an appearance some 20 odd years ago. They are extremely simple transceivers that use the TX PA as the RX mixer to save parts.
I built a Micro 80 some years ago and my best QSO was around 300km. Biggest issue (for me) was broadcast breakthrough from strong broadcasters just above the 80m band. Variations included the Pixie 2 which added some refinements at the expense of more parts. Kits are available, but the circuits are so simple it is not work paying over the odds for these. The Micro 80 uses all discrete components whereas the Pixie and Pixie 2 use an LM386 for the RX audio.
If you build one, be prepared to fight for contacts. It is not the TX power that is the problem: it is the receiver that is the limitation.Given good conditions and little broadcast breakthrough, these rigs work.
See https://sites.google.com/site/g3xbmqrp3/hf/pixie .
The same basic schematic will work on any HF band with changes to the output filter. Watch out for chirp on the higher HF bands: don’t be tempted to try to pull the crystal too much, especially on the higher HF bands.
David Sumner, K1ZZ, speaks to Norfolk ARC
David Sumner, K1ZZ, of the ARRL presented a presentation “Amateur Radio Across the Pond” to the Norfolk Amateur Radio Club in the UK. I thought the hour-long presentation was quite enjoyable.
X108 20W transceiver
G1KQH informs me this Chinese transceiver is available for an introductory prce of £399.99. Personally I think this is MORE than I would expect. To me it still looks like a “back shed” design. I notice this supplier has sold out.
This is an introductory price for the basic version without TCXO and noise blanker. The FT817ND is now available for well below £500 with cash back offers and, to my mind, is a well proven MF-UHF design.
The X108 claims ” minimalist industrial design”. Read NO industrial design in my book! Still waiting for the Chinese “killer” radio to out-smart the Japanese. This, in my opinion, is not it.
Morse code chat room
Just when you thought you’ve seen (nearly) everything….
If you use the Chrome browser (for best results, apparently), check this out:














