GBPPR Ideas


"If everyone is thinking alike, then no one is thinking"  -- General George S. Patton, Jr. (1885 - 1945)

Cybiko

Cybikos are cool.

Frequency Converters

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.

Quantum Entanglement

Use the spin states of entangled electrons to propagate information over long distances.  Use the spin states to represent binary data.

Alternative Power Sources

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The typical amateur approach to EME (Earth-Moon-Earth) contacts is "brute force" RF power and outdated modulation methods.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...

Soundmodem

http://www.baycom.org/~tom/ham/soundmodem

Example sound modem script

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