Author: HAM RADIO SITE

Velocity Factor of Coax 0

Velocity Factor of Coax

“The velocity factor (VF), also called wave propagation speed or velocity of propagation, of a transmission medium, is the speed at which a wavefront (of an acoustic signal, for example, or an electromagnetic signal,...

A Simple 40m Vertical Antenna 0

A Simple 40m Vertical Antenna

The 40m band is a great place for DXing! I don’t have the tall supports needed for a dipole or beam, so a vertical antenna works best for me. I do have a convienent...

Variable Power Supply Unit. 0

Variable Power Supply Unit. DIY.

This little circuit is a copy of a design which was built around twenty years ago. The heart of the unit is based around a 723 regulator chip. It has variable voltage and current...

6m to10m converter 0

6m to 10m converter

This circuit is based around mixer/oscillator IC2. A 50mHz signal is fed to pin1 input of IC2 and mixed with the local oscillator injected at pin7. The resultant output is the antenna frequency minus...