Well, after some help from the Minimalist-QRP yahoo group and members of the #technest freenode 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.
The wave form does look a bit wonky down the low end, but is a lovely sinusoid at about 1vp-p from about 7.08 up.
Will have to wait until payday to get the next lot of bits from Jaycar to continue building, but it’s been fun so far :)
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