Ready References
Essential Technologies for Making Accurate PC-Based Measurements
Variable Stars Explained
Signal Generators and Their Uses
The Use of Fused Silica
Age of the Earth
King of the Amateurs
Understanding Celestial Coordinates
Ready References Essential Technologies for Making Accurate PC-Based Measurements Variable Stars Explained Signal Generators and Their Uses 
The Use of Fused Silica Age of the Earth King of the Amateurs Understanding Celestial Coordinates