[Laser] Using a Coleman inverter for modulating fluorescent or HPS lamps

[Andrew T. Flowers, K0SM]

Kerry,

You might consider the DDS-60 kits from the AM QRP club for an HF 
frequency source.  I've use them as frequency references for PLL brick 
oscillators (replacing the on-board reference with an OCXO), but it 
would also be useful for this project.  Best of all it comes in a kit 
and can be controlled by the parallel port.

http://www.amqrp.org/kits/dds60/

-Andy K0SM/2


Kerry Banke wrote:

>  The next step is to replace the  9MHz signal generator with the VCO 
> section of a 74HC4046 PLL IC and phase lock the inverter frequency to 
> the audio output of my laptop.  I'll distribute the modifications 
> after I complete the project shortly. The intent is to provide a 
> fairly easy way for others to experiment with sending text via 
> ordinary lamps using free software  which generate sequential tones in 
> a narrow bandwidth such as Laserscatter, Jason, etc.  . The scheme 
> works with most any incandescent, fluorescent ( without high frequency 
> ballast) and HPS lamps with each type having more or less modulation 
> efficiency.