Another experimental wireless data project. Should be easy to build (if it works), data rates could even hit 115.2 kbps. Frequency is arbitrary, and is only limited by bandwidth/bandplan considerations.
None of this has been built yet until I can figure out a few bugs.
I have no idea how to properly inject RS-232 (serial port) data into a VCO, if you know how to do this, please contact me. The whole loop filter/data injection area is quite flaky.
On the receive side, I not sure what to do with the data slicer output signal, I'm just amplifying it and applying it to a MAX232.
I'm also not sure where to get a good PTT signal from computer's serial port.
Some of the parts can be found in old cellular phones (964 MHz VCO and filter), 900 MHz cordless phones (903/927 MHz filters and IF filters). Everything else should be easy to track down.
- Transmit section block diagram (42k PNG)
- Receive section block diagram (45k PNG)
- Alternative transmit section block diagram (42k PNG)
- Alternative receive section block diagram (60k PNG)
Return to Green Bay Professional Packet Radio for more info and contact information.