Misc info and opinions
Someone asked how does the price compare to buying COTS ready to go equipment... Well, that's not really the goal with me. If it were, I would be buying a used Cessna or Piper and save a ton of cash over building my own -- Fly it away 10 minutes after closing the purchase. Its about the learning and "tinkering". I do not consider a GPS unit and moving map a critical system for VFR flight. I consider it a luxury... Thus I have no issues with doing this type of stuff. I am taking it slow on this build and don't mind being side tracked by electronic projects or alternative engine research/fabrication.
Honestly, some of the guys on here crack me up with their attitudes toward anything that does not get Vans written endorsement (and thus sales mark-up). Someone who is capable of taking a flat pile of aluminum and rivets and construction a flying machine should be capable of almost anything else "alternative" discussed here. The word alternative is in quotes because it is synonymous with "experimental" to me.
Where would we be today (in this hobby) without previous nut-jobs (I say that with utmost respect) who understood what "experimantal" meant. Besides, after following Vans instructions to the LETTER for many thousands of hours building the airframe, some of you could use the unbridled excitement of a Yugo engine driving a tractor differential for a PSRU, radiators flapping in the wind, an old commodore vic-20 handling the instrumentation/GPS/autopilot duties, and some old floppy drive motors acting as autopilot servos.... That's flying !!!
Plane PC stuff is cool, but way expensive. I do, however, like the way they mount the monitor in a couple of their pictures.
You can source the same parts for less and fabricate the monitor mounting. Again, being capable of building an aircraft should mean you are capable of this type of stuff as well... if not, you might want to buy off the shelf parts and send them to whoever is constructing your plane!
Someone asked about GPS.. I will reply privately, but here are a couple of the type of quick updating, sensitive, accurate, cheap receivers I am talking about. You can either run 2 of these units to the PC or I devised for myself a small reliable circuit board (Pic based) that provides auto or manual GPS redundancy, redundant regulated power to the receivers, and a small remote LCD display (for status of both GPS units -- parsed lat, long, GPS time, and speed/altitude can also be displayed for both units as well). Or you could have a script running on the PC itself that parses the NMEA sentences for correct format, monitors lock status of the GPS and makes a decision to throw a relay to take the output of the backup GPS if something is not right with the primary. The relay can be thrown from a pair of parallel port or serial port pins being toggled.
32 channel DGPS/WAAS/EGNOS, 5 Hz:
http://www.sparkfun.com/commerce/product_info.php?products_id=8266
54 channel WAAS/EGNOS, 1Hz standard, 5Hz optional
http://www.sparkfun.com/commerce/product_info.php?products_id=8703
I have used many of the 32 channel models in several applications without a single failure... that is from dirty 12v power with cheap home made DC-DC converters. They work great.
Sparkfun is great! Take a look at the micro sized, highly accurate UAV platform they have for sale. You could program that sucker to fly your plane to a specified location and circle for you in an emergency. Add a couple sensors to monitor for stick pressure or something to determine if the pilot is in control or not...It could also activate an ELT... Maybe better than an automatic auger maneuver. Or heck, just use it to build a cruise missile out of stuff in the VAF classified forum. Whatever floats your boat!
