I previously listed a video with a Ring down Q Meter, that was designed by a fellow in China and sold by mkmak222 on Ebay, he was down to six the last time I heard.
The same fellow in China has designed a new Ring Down Q Meter, I don't new what the new spec's are, and in my conversation with mkmak222, mkmak ask him to produce it for sale and he declined. There is a website with a schematic and picture of the PCB and loads of info. It uses an atmega88-20au, I don't know if the code is on the website. The page is in Chinese, so you will need to translate, I have not tried, so know how good the translation is. I see a picture of the front it says 400kHz to 10 MHz. 30 Q to 2500 Q .
http://www.crystalradio.cn/thread-1613531-1-1.html
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