I know I can modulate a laser using an audio transformer see pic and website below. Pen Laser website

image of pen laser

I was wondering if it’s possible to modulate a simple pen laser using RF signals in the RF range of 1Mhz-100Mhz range?

I was thinking of replacing the audio transformer with a RF transformer and using a function generator to generate the RF signal. Here’s the RF transformer I was looking at. RF Transformer Is this possible?

RF Thoughts

Would a solar cell connected to an an oscilloscope work as a receiver at such high frequencies see pic? (I would replace the stereo with an oscilloscope)


  • \$\begingroup\$ That's an interesting design. Whether or not it will work at such a high frequency will depend heavily on the circuit inside the laser. The laser can probably do that theoretically. \$\endgroup\$
    – Drew
    Oct 6, 2018 at 1:06
  • \$\begingroup\$ The laser is probably capable of it. The circuitry in the laser pen not so much. This is the point where you have to stop and realize that you've left "the instructables zone" and are going to have to learn more about what is going on and how it works. The thing the transformer is a real squinky hack that works, though not well. It relies on a lot of unwritten assumptions about the laser pen, the transformer, the power supply, the solar cell, and the stereo. It happens to all work out to something functional - unless you try to use in the sunlight or break any one of the assumptions. \$\endgroup\$
    – JRE
    Oct 6, 2018 at 9:08


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