Re: LF: RE: Analog oscillators

["Roelof Bakker" <roelof@ndb.demon.nl>]

Hello Stefan,

The NE602 works very well as oscillator and delivers a clean and low noise  
signal.
One of the main problem in building VFO's is the mechanical design.
It can be done, but it is not trivial when you use a tuning capacitor and  
gearbox.
Mechanical rigidity and freedom from micropfonics requires a solid  
enclosure which with the gearbox need to be mounted on the frontpanel,  
rather than on the chassis.
As the frequency range is small, it will be mechanically much easier to  
use varactor tuning in conjunction with a ten turn potmeter. I have been  
there and done it all.
I have build a 40 m receiver with varactor tuning and it is rock stable.

Building VFO's is fun!

73,
Roelof, pa0rdt