I agree 100%. Here are some other hardware related subreddits I follow.
ECE
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http://www.reddit.com/r/electronics
http://www.reddit.com/r/AskElectronics
http://www.reddit.com/r/ECEComponentExchange
RF
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http://www.reddit.com/r/RTLSDR
http://www.reddit.com/r/GNURadio
http://www.reddit.com/r/rfelectronics
Maker
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