GPS RECEIVERS vs 60KFT
Ralph Wallio, WØRPK W0RPK at netINS.net
Updated 06Sep08


The 60kft limit (aka 18km) is one of the three vehicle dynamics limitations placed on GPS receivers for we civilian unwashed, altitude, vehicle velocity and acceleration.  GPS receiver manufacturers are allowed some leeway to juggle the values of these limits to serve their markets so details vary between manufacturers, between models from the same manufacturer and even between software versions in the same model.  The 60kft (18km) upper limit of controlled airspace is the altitude limit most often used.

Amateur high altitude balloonists have discovered a few GPS receivers that allow operation above 60kft and often announce their findings to our small community.  I have yet to hear of balloonists using expensive GPS simulators for this test so this knowledge results from actually flying receivers above 60kft and experiencing the results.  This web page is intended to gather first person information submitted by individuals and groups that have tested receivers.

We will need to be picky about models, software versions and dates so submitted information will need to include:

Manufacturer
Model number (complete)
Software version (often output at power-up)
Individual or group involved in test
Date of test
Test result (Pass or fail)
Other relevant information


RECEIVERS THAT PASS THE 60KFT TEST

MANUFACTURER

MODEL

SOFTWARE

TESTED BY

TEST DATE

DATE POSTED

DeLorme

TripMate

(Rockwell ZODIAC chip set and commands)

TBD

ARSAT (N5SNN)

10Sep05

18Mar06

FASTRAX
See Notes [3] [7]

iTrax02

V 1.11

AMSAT-France
(F6FAO)

15May04

18May04

GARMIN

ETrex

2.11

KMC
(Pioneer Astro)

17Apr02

13Jun02

GARMIN

GEKO 201

V 2.0

TVNSP
(KD7OST)

TV03G 12Jul03

13Jul03

GARMIN

GPS-16-HVS

2.3.0 & 2.9.0

TVNSP

(N7MTZ & W7MJR)

04Jul04

05Jul04

GARMIN [Note 9]

GPS-18-LVC

2.30 & 2.40

 TVNSP
(KC7DBA)

06Nov04

14Nov04

GARMIN

GPS-25 LP-LVS

GPS 25-LVS V2.5

F1SRX

12Jun2003

30Jan04

GARMIN

 

RINO

TBD

HABITAT SKYLAB

(KAØJLF)

01Aug04

03Aug04

GARMIN

GPS-35HVS

GPS 25-HVS V2.5

WØZC

22Apr01

05May01

GARMIN

GPS-15H

2.70

KB8PVR

09Apr05

19Apr05

MOTOROLA

GT+ ONCORE [5]

NA

KI5CZ

1998

07Dec04

MOTOROLA

M12
P183T12N12

61-G10002A
Ver.1 Rev. 3

ANSR
(KD7LMO)

 

12Jan03

MOTOROLA

M12+
P283T12N15 

61-G10002A
Ver.1 Rev. 8

ANSR
(KD7LMO)

07Dec02

12Dec02

NAVMAN

 

JUPITER 32

(SiRF III chipset)

GSW3.2.4-SDKNM_3.1.00.12-SDK001P1.00a
Jupiter32 v2.1 build 1 (S3)

ANSR

(KD7LMO)

15Dec07

31Dec07

RAND McNALLY

 

Streetfinder GPS for the Palm III

(ROCKWELL ZODIAC)

ZODIAC V1.83

ORB

(KC5TRB)

ORB-5 14Sep03

18Sep03

ROCKWELL
(CONEXANT)

JUPITER
TU30-D140-221/231
[Note 6]

JUP V1.80
CRC:CFB5

EOSS
(W5VSI)

EOSS-39 12Mar00 thru -49 21Apr01

08May01

TRIMBLE

LASSEN LP GPS P/N 39263-00

7.82

BEAR
(VE6SBS)

BEAR-1 27May00
BEAR-2
05Aug00

23Jun01


RECEIVERS THAT FAIL THE 60KFT TEST

MANUFACTURER

MODEL

SOFTWARE

TESTED BY

TEST DATE

DATE POSTED

 AXIOM

SandPiper

SiRF Star-1 chipset

[1]

 unk

 

 DELUO

(rebranded EVERMORE)

Note [4]

Serial GPS

Unknown

EOSS-83

(KØANI)

08Aug04

09Aug04

 DELUO

 

Lite

Unknown

(Sony chipset)

K5IS

16Apr05

28Apr05

 GARMIN

 

GPS-45

3.05

EOSS
(KCØJHQ, N7QAM)

26Sep01

10Jan02

HOLUX

GM-210 [1]

(SiRF-II chip set)

 $Version 2.3.2-GSW2-2.05.024-C1Prod1.1

$SiRF version : 2.3.2 uservesion : GM210V41

TABEL

KE4PJW/KQ4TV

22Apr06

01Jul06

28Jul06

HOLUX

GR-213

(SiRF-III chip set)

 Also failed

Info pending

TABEL

KE4PJW/KQ4TV

01Jul06

28Jul06

 RADIO SHACK

DigiTraveler

 

Note [2]

 

 

ROCKWELL
(CONEXANT)

 JUPITER
TU30-D140-061
[Note 6]

JUP V1.03

EOSS
(KCØYA)

 

24Jan06

SAN JOSE
NAVIGATION

FV-17
(FURUNO GN-79N)

Unknown

 

Alfred Kastler school
(F5FJA/F6FAO –
France)

13May04

02Jun04

 

TELIT

(24km ~80kft  alt limit)

GM862-GPS

(SIRF-III)

Unknown

EDGAR-1

(VA2TCV)

05Apr08

20May08

BYONICS

GPS2

SiRF-III

Notes [1 & 8]

LASA

24Nov07

27Nov07

Note [1]            We now have solid evidence that GPS receivers based on SiRF-I and SiRF-II chip sets all fail at ~60kft.  Some SiRF-III chips sets, receivers that use them and firmware work at high altitude –but- others do not.    

Note [2]            We have a report that a Radio Shack DigiTraveler GPS receiver max’ed-out at 9,999m but continued with reliable 2D navigation.

Note [3]            Warning de F6FAO: To have the GPS working above 18 km, you need to send a command to the GPS. This command is ‘Set Upper Limit’.

Note [4]            The DeLuo Serial GPS receiver is a discontinued product but DeLuo continues to sell a few EverMore GPS receivers.  It appears all EverMore receivers are limited to 18km altitude.  Some other DeLuo GPS receivers are based on either the SiRF Star-I or SiRF Star-II chip sets which are limited to 18km per above.

Note [5]            Motorola GT OnCore receivers in both 6-channel (earlier) and 8-channel (later) versions were successfully flown above 18km by FreeSpace, and HABET (ISGC/ISU).  Model numbers and software versions are no longer available.

Note [6]            From Steve KCØYA of EOSS: Early Rockwell Jupiter boards, serial numbers <300,000 with V1.03 software, have failed above 30km.  Later boards, serial numbers >386,000 with V1.80 software, have repeatedly worked ok.  Contact Steve for more details. 

Note [7]            Gerard Auvray, F6FAO, forwards the following information from FASTRAX support:

De : Fastrax Customer Support [mailto:support@fastrax.fi]
Envoyé : lundi 21 mai 2007 16:33
À : AUVRAY GERARD; Fastrax Customer Support
Objet : RE: Max altitude for GPS

Hello Gerard,

 

The following receivers can be used above 18 km:

 

iTrax03

iTrax03-s

iTrax130

uPatch130 (new receiver, available beginning of Q2)

 

They all work if speed is < 1000 knots

 

http://isuite.fastrax.fi/faq.html#mozTocId469010

 

Other receivers limit the height to either 20 km (uPath101,102) or 60000 feet (All Sirf based receivers like iTrax300, uPatch300) regardless of speed.

 

The only receiver actually tested above 18km in a real application (in a weather balloon) is iTrax03.

 

 Note [8]           Byonics GPS2 cut out when the payload ascended beyond 78,838', and resumed
after burst when it descended below the same level one hour later.  – Rick LASA

Note [9]            On 23Aug08 a new GPS18xLVC froze altitude at 60kft.  Garmin development staff found the software problem
which will be fixed in the next software release.

 


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