are there diy plans for a speed measument device?

[jeff262]

i have tried the search feature but i keep getting the " Your pevious search is still running please hit the back button" so i just thought i would ask if anyone know of previous threads about diy speed meter devices, either on your plane your radar type. any info here would be great
thanks jeff

[jeffs555]

If you are after a radar gun, there are usually quite a few Bushnell Velocity guns on ebay for buy it now prices around $90. For onboard speed sensors, you would either need some kind of data transmitter, or or else a micro to log the speed. The only thread I have seen recently was about using audio doppler shift to measure the speed. http://www.rcgroups.com/forums/showthread.php?t=308120

[soren]

Hi
Look at:
http://rc-stahl.bei.t-online.de/bc_src/bcomp_frm.html
http://home.arcor.de/d_meissner/d_logger.htm
http://www.rconline.net/magazin-2000/daten-logger/daten-logger.shtml
http://www.rcgroups.com/forums/showthread.php?s=&postid=1099124#post1099124
http://www.mp.ttu.ee/risto/rc/electronics/index.htm

Soren

[Thud_Driver]

Maybe what you are looking for is for somebody to design a simple airspeed telemetry system out of these:

http://www.laipac.com/easy_434_eng.htm

Could be something like a vane on a pot (AOA) or a pressure transducer (airspeed) doing a variable pulse width or frequency with, say, a 555 timer chip, or such, feeding the Tx at the airplane. Then doing a conversion to a variable audio tone/beeper on an earpiece or speaker in your shirt pocket. I'd prefer to see discrete components versus a PIC project, but a more complex PIC project could do an airspeed or AOA readout. But then you'd have to calibrate it. Range is 300 to 500 feet which is more than enough for takeoff's, landings or low passes.