Low power radio handbooks and guides in PDF

Exploring the digital attic, found some volumes dedicated to low power radio that you just might find useful; audio amplifiers for AM transmitters and a some great information about antenna matching, coil winding, RF grounds and general low power radio hints and tips - enjoy!
Need a quick circuit for a simple audio amp?
• Integrated Circuit Audio Amplifiers By Mike Martell N1HFX
Can there be too many readings about antenna coils?
• Construction of Antenna Matching Transformers
• Loading Coils for Low Power AM Antennas
General low power info
• Joe Carr's Radio Tech-Notes - What is a "Good Ground?"
• Hints for Low Power Broadcasters
• Low Power Radio hints and tips booklet
Hard core audio modulation for AM
• Modulation Transformers
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