This page is under construction and will concentrate on analog VFO designs.  First will be the Franklin and the Vackar designs will be next

The Franklin Oscillator is little known but simple and very stable, all the way up to 10 meters.  Some examples are below.

The Franklin Oscillator, January, 1940, Radio Magazine, page 41 

A Franklin design from the July ’64 QST Magazine

Here’s a solid state Franklin from the February, 1999 QST

An example of a Franklin oscillator integrated into a portable xmtr is here.

SV3ORA offers simple and more complex versions of the Franklin VFO.

Here’s a Franklin VFO that uses 6088 miniature tubes.

Some Franklin discussion and examples are here.

Another Franklin; uses a lot of DIP switches!

Using a 250 pf BC-221 100:1 Geared Tuning Capacitor in a Franklin circuit.

Yet another Franklin is here.

Next, let’s look at some Vackar Designs:

First, some Wikipedia definition about Vackars.

A Vackar design from qsl.net; includes a component value spreadsheet

This one uses the 12AT7 tube and glows in the dark!

A solid state Vackar by VA3DIW

Stable Transistor VFO’s:  Vackar and Seiler