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ZAZ
13th Feb 2016, 23:13
FYI:
In commercial radio we use the following

Byonics GPS Receivers
http://www.byonics.com/images/gps4.300.png (http://www.byonics.com/images/gps4.png) Byonics GPS receivers are 5-volt, WAAS enabled, WGS84, output 4800 baud NMEA 0183 serial and employ the SiRFStarIII chipset tracking up to 20 satellites. They are compatible with any d clam shell rs232 interface like we use for barometric input to a GNC300, e.g. , all of which provide the 5V to power the GPS directly. They have a female DB-9 connector interface on a 6 foot cable, and the cases are weather resistant so they are fine in the rain, snow and sun, and contain a magnet to be easily mounted outside a vehicle. However, they are sensitive enough to work well even indoors.

A blue LED is inside the case that is on solid then aquiring, and flashes once synced to the satellites. DB-9 pinout is 2:GPS data out (RS-232), 3:GPS data in (not normally used), 4:+5V power input, 5:ground. Current draw is about 40mA. NMEA sentences sent each second: $GPGSA, $GPRMC, $GPGGA, $GPGSV. Accuracy is approx. 5 meters with WAAS. Acquisition times are: Cold Start: 42 sec (avg), Warm Start: 38 sec (avg), Hot Start: 1 sec (min). Sensitivity is Acquisition:-148dBm, Tracking:-159dBm.

(check these specs and you will see they are EXACTLY same as quoted in aviation products surprise surprise).

The COST $65 USD.
These are used for orienteering safety and life in remote bushland tracking and attached to marine shipboard comm's tracking via AIS shipping by coastal VHF repeaters
but NOTE not to be interfaced to devices like the 430 non was for for flying which as we know is so dangerous that we can never use a non certified device.
I have been told that avionics developers have acquired the similar module with WAAS and fitted inside of transponders and interfaces for GNS systems attach an AVIATION certification to them and then charge a $1000 extra.

http://www.byonics.com/images/gps3.140.jpg
GPS OEM 5 $49.00


To fly in the world of WAAS, aircraft must be equipped with


a receiver meeting the requirements of TSO-C145a or


TSO-C146a. How expensive and complicated will this be?




$994 development costs I guess.








So users of cheap after market waas gps readouts like these you are never to use them for navigation!!
You have to buy the certified device to be safe and sure.
Breaks me up to see the high cost and rorting by aviation use of a common technology generally available and as soon as you attach an AVIATION status to it the whole set of rules change just to ensure you don't fly into a hill using an non approved gadget.



Dig deep you rich aviators you can afford to support the industry no matter what...

LME (GOD)
16th Feb 2016, 12:20
So...your point is what? Commercial of the shelf products are cheaper that items approved to TSO or eTSO standards?
The reason for this is the approval and testing requirements to get COTS products approved for use in aviation are lengthy, extensive and expensive. A component on an aircraft must meet numerous set criteria like EMC interference, flammability, redundancy for critical systems, continuing inspection, technical manuals, software approval to name a few.

That's what the extra money goes into.:ok:

aterpster
16th Feb 2016, 13:50
Alerting, continuity, and integrity come to mind.

Having WAAS provides augmentation to the space-based system. It does not provide the complex stuff, such as LPV.

7478ti
22nd Feb 2016, 06:37
With 30+ GPS SVs, and evolving 30+ Galileo and other SVs, and modern Kalman filters, and especially with networks of GBAS/GLS (which are needed globally for other reasons, for the next few centuries at least - e.g, FMEA and FHA elements like the 1000 year solar event)... WAAS is an utterly obsolete useless waste of money, that needs to atrophy and be put out of its misery at the earliest opportunity (unless of course somebody in GA or some other foolish taxpayer, or avionics company is willing to continue to personally foot the bill for it). The same goes for LPV (Laterally polluting vermin), which as another utterly obsolete angular artifact of obsolete TERPS and CRM (8260.3 as amended) ... LPV's "angular-straight-in" surfaces do absolutely NOTHING for solving airspace or approach issues, that RNP can't do better, simplier, cheaper, quicker, and SAFER (because ONLY RNP does the analysis for normal, rare-normal, and non-normal ops properly, both into the runway to the TDZ, and back out, 100% of the time).