Cybikos are cool.
It might be possible to convert 2.4 GHz or 915 MHz wireless LAN devices to much lower frequencies like 400 MHz using common parts.
Use the VCO and PLL from a MMDS downconverter.
Use the spin states of entangled electrons to propagate information over long distances. Use the spin states to represent binary data.
Alternative Power Sources
- Low level chemical reaction powered by human body heat
- Nano-flywheels powering tiny batteries
- Capture the motion of a person's moving legs/feet to charge batteries
- Thermal electronicvoltaic - Power a flame using methane gas (garbage) and place it near a solar cell
- Capture the flux between Jupiter and one of its moons
- Capture charged photons in the solar wind
Proxim RangeLAN Bridge Modifications
It is possible to increase the Proxim RangeLAN bridge's RF output power from 500 mW to over 1 Watt. Refer to the PM2107 datasheet for more info.
Here's someone who documented this modification.
Effective Moon Bounce Contacts
The typical amateur approach to EME (Earth-Moon-Earth) contacts is "brute force" RF power and outdated modulation methods. As usual, these schemes are wrong.
It is possible to use direct sequence spread spectrum techniques, along with on/off keyed morse code, to conduct moon bounce radio contacts at a slightly lower effective radiated power (ERP). Using the processing gain of direct sequence spread spectrum systems (example, 3 dB) will allow you to reduce your overall ERP by 3 dB.
This is essentially how GPS systems work. Their processing gain is quite high, 40 dB or more.
Phil Karn expains it better.
30 dBi Parabolic Dish for 2.4 GHz
It is possible to use those old, 6-foot, parabolic C-band dishes at 2.4 GHz. Just mount a 2.4 GHz dipole at the focal point (or a PCMCIA card hehe) and bingo, a cheap 30 dBi antenna. Have fun mounting that on the side of your tower...
Example sound modem script
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