Check'in

GPS Free-Flight Verification System

Christian Quest (cquest@cquest.org) - 8-Apr-2002

Hardware support

"GPS flight verification should support all hardware used by the pilots and organizers"

Content

Home - Top

 

Computer requirements

Home - Top

Check'in works on both Macintosh running MacOs and PC running Windows to let the organizer choose which kind of computer they want to use.

Macintosh: any PowerPC based Macintosh (PowerPC G3 recommended). 32MB of free RAM (64MB recommended)

PC: any Pentium PC (Pentium 200 and above recommended), 64 MB of RAM (or more depending on the Windows version installed)

Serial ports and GPS cables are required to transfer track logs from GPS receivers (see below).

 

GPS receivers

Home - Top

Check'in support the following GPS receivers or flight recorder/dataloggers:

Garmin models like the eTrek (basic model), eTrex Summit, eTrex Camo and the eMap must be avoided as their tracklog recording parameters cannot be changed (it only work in "auto" mode).

Garmin models have been used for a couple of years by the pilots. Their memory is limited compared to the TopNavigator and the MLR units.

The high-end eTrex models (Legend, Venture, Vista and also the Garmin 76) allows time interval based tracklog recording and are supported by CheckIn starting with release 18. They use a different plug that the older Garmùin models.

The Top Navigator is a "all in one" unit that includes altimeter, variometer, air speed, thermometer and GPS. It has been specially designed a few years ago for hang-gliders and paragliders. It can record very long flights and will provide a tracklog with a 10s resolution.

The MLR SP24XC unit is a new model made by a french company which included all specifications required for flight-verification:

This model also offer a 36h autonomy and has roughtly the same size/weight as a Garmin 12.

 

Here is a summary of the features of most common supported models:

Model

Tracklog points

Altitude recording

WAAS*

Fast download**

Comment

Garmin 12, 12XL, GPS II+

1024

N

N

N

Garmin 12CX

2048

N

N

N

Garmin 12MAP, GPS III+

1900

N

N

N

GPS III

2000

N

N

N

Garmin II,38,45, 48

768 or less

N

N

N

no valid for goal time

eTrex Venture & Legend

2048

Y

Y

N

eTrex Vista

3000

Y

Y

N

eTrex Mariner

?

?

N

GPS 76 or MAP76

?

?

N

Garmin V

3000

Y

Y

N

CheckIn 1.0.21 and above required

MLR SP24XC

8000

Y

N

Y

4000 tracklog points in versions prior to 2.7

Aircotec Top Navigator

4000

Y

N

Y

Renschler SOL with integretad datalogger

40000

Y

-

Y

needs external GPS

RUAG datalogger

32000

Y

-

Y

needs external GPS

* WAAS (Wide Area Augmentation System): it is a new differential system that provides position accuracy of 3m instead of 15m with classical 12 channels receivers.

** Fast: download: download tracklog are a rate of more than 4000 points par minute compared to the "slow" Garmin protocol that support between 600 and 1200 points transfered per minutes.

 

Firmware upgrades

Some GPS reveiver internal firmawe may be required for Check'in to work properly. Models that cannot be upgraded (ex: Garmin 38, 40, 45) should be avoided.

On Garmin models, some units need to be updated mostly to fix internal firmware bugs. See Garmin web site for more details. It is highly recommended to use the latest firmware update if you want accurate time being recorded by your GPS.

On Top Navigator, be sure to have the Year2000 update as this update also contains a new tracklog transfer format called "PWC" whichi allows fast download.

On MLR SP24XC, you must have a "free-flight" firmware.

  

Cables

Home - Top

It is highly recommended to use cables made by the GPS manufacturers because they generally are much better quality compared to "compatible" or home made ones.

This is important as you'll plug/unplug these cables many times and loose contact will cause a lot of download errors.

So, get Garmin cables for Garmin GPS and MLR ones for MLR GPS. The Top Navigator is sold with all cables included.

Be cautious with MLR cables are their "male" pins are more fragile than the Garmin "female" plug.

 

Serial ports

Home - Top

All current GPS receivers communicate with computers using serial communications. This means that your computer must have free serial ports on which you'll connect the GPS using special cables.

Most computer have built-in serial ports, but it is becoming more and more usual to find computers that have no serial ports.

In order to download several GPS in parallel, you'll need as many serial ports as the number of GPS you want to download simultaneously.

For the above two reasons, you may have to add serial ports to your computer using some card or adapter (see below).

Check'in supports built-in serial ports and several kind of additional serial ports:

The simplest to setup is the last one, the USB adapter. It works on both desktop and laptop computers, on PC and Macintosh. It is the most universal solution I've used so far.

I highly recommend you to have a look at the Edgeport from IO Networks which provides 2, 4 or 8 additional serial ports. It doesn't need an external power supply (usefull if you plan to do GPS flight verification on the landing field with a laptop) and is very easy to setup (thanks to USB plug-and-play feature). I cannot guarantee that CheckIn will work with other equipments as some of them have very badly written drivers.

Keyspan have a similar product (4 serial DB9 ports).

CQ-8/Apr/2002