Power Supplies

• DC power supply
• Power Circuits
• 6CA4 Power Suply
• Tube Power Supply Design
• 8 Simple Power Supplies
• Electronics Basics Link from Girl Scouts

Oscillators

• Hartley Oscillator
• Types of Oscillators
• Vacuum Tube Recievers and Transmitters
• Crystal Sets to Sideband
• Superhetrodyne First Detectors and Oscillators
• Tuned Plate, Tuned Grid, Hartley, Colpitts, Electron-Coupled and Negative Transconductance Oscillators

Waveguides

• How To Build A Tin Can Waveguide WiFi Antenna
• "Mobile Amateur (Doppler) Rain Radar" Project
• How to build “cantenna”, a wave guide antenna out of a coffee can