VHF/UHF Signal Generator
 
 
 
The signal generator shown was designed around a TV tuner by bringing out the signal from the local oscillator.  The operation of the tuner remained as designed and continued to function as an RF converter.  External circuitry was added to provide a sweep function, a 1Khz sinewave for standard deviation FM modulation in addition to the normal CW signal.  An MMIC amplifier was placed between the local oscillator and the output to provide up to 5V of output signal.  The 10 turn pot allowed smooth tuning over each of three ranges covering a total range of 100-1000Mhz. 

When in use, the generator may be used in several functions: Signal generator, frequency converter, sweep generator and a  spectrum analyzer.  

The pictures are the only ones taken during the construction period, and unfortunately, of poor quality. 

Click on the image to enlarge.

 
This view was taken before all of the parts were mounted and the panel marked.  The box to the right was the shield for the output amplifier, attenuator and connector.  It was made of tin can material. 
Top view before the wiring was added.  The board contains the sweep circuitry, audio generator and power supply. 

The coax connectors on the rear are for I.F. output, VHF input, UHF input, and on the far right is the sync output to the scope sweep.

This view shows the markings on the front panel.  The small knob slightly to the right of center is the vernier frequency adjustment. 

The bandswitch is in the upper left, and the sweep and deviation control is below the bandswitch.

 

This is a top view after completion of all wiring.

 

This is an oblique view to show the simplicity of the design.

 
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