Over the last few weeks I've debugged my Beach40 a bit! I found that I'd stuck in the wrong size resistor on the lm386 feedback circuit, 2.2 Ohms, vs the needed 2.2 kilo-Ohms! So, with that fixed, it worked a bit better!
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Well, the Beach40 is boxed up and ready to test! Just working out what else I need to check before putting it on the air! Hopefully I'll be set up at 04:00 UTC tomorrow (2014-07-08), listen out somewhere between 7.007 and 7.230 :)
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Had a bit of a quiet weekend, didn't get a huge amount of radio stuff done, instead mostly housework, looking after the kids and on call work!
However, I got my dummy load built:
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Well, the soldering is finished anyway! Still have to find a box, get all the connecting hardware, shield the oscillator, and build the L-Match circuit (and maybe the fine tuning circuit, and RF pre-amp).
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Have got my Beach40's mic amplifier in, and tweaked the carrier suppression via the balance pot and cap. I'm managing a carrier suppression of 24 dB, which i don't think is too bad for a first time homebrew build, but I do need to get some non-capacitative flathead drivers, would make these things a bit easier!
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Well, I finally collected all the extra bits I needed, and had an hour or two to proceed further with my Beach40 build, and got my recieve audio amplifier circuit built:
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Stuffed a few more bits on the beach40. Got the ring mixer in, and the first transformer. Also managed to solder a SOIC-8 chip to a MePad :)
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Well, after some help from the [Minimalist-QRP](https://groups.yahoo.com/neo/groups/Minimalist_QRP_Transceivers/info) yahoo group and members of the #technest irc channel, I've got my oscillator going a bit better!
It now covers from 7.0041 MHz to 7.2405 MHz, a much more useful range of the 40m band!
In the end I used two 7.2 MHz ceramic resonators in parallel, with the O leg of a jaycar varicap and a 1 µH inductor in series with that.
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I've started building Peter Parker [VK3YE](http://vk3ye.com)'s 40m Dual Side Band transciever, completing the oscillator Manhattan Style:
I've built it with some 7.2MHz resonators from [MiniKits](http://minikits.com.au), and with the 60-160 pF variable cap I have, it gets me from 6.938MHz to 7.049MHz. Which is not terribly useful for the 20m band (7.0 -> 7.3 MHz). So I'll have to tweak things and work out how to get more swing from the oscillator.
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