SparkFun Forums

[zerog]

Hello!! First post!! I've just received the Trimble Lassen IQ module i ordered form Sparkfun. I connected the module to Arduino board and i'm able to receive and process GGA strings. I need to use the module for a high altitude balloon flight, so i need to be sure that there isn't limit for altitude measurement.
I read on the datasheet that the limit for altitude is 18000 m and the speed limit is 515 m/s. The question is: have i to configure the module to allow altitude measurement without limits? If yes, how? I can't find anywhere this procedure! :think:
Thanks for your attention!!

[MichaelN]

You will find it very difficult to remove this limitation, as US law requires this to prevent modules from being used in ballistic missiles etc.

Most manufacturers interpret the rules to mean simultaneously exceeding the speed and altitude isn't permitted. In this case you'll be OK as the balloon won't exceed the speed limit. Apparently the Lassen falls into this category. Some manufacturers instead interpret the rules to mean exceeding EITHER speed or altitude isn’t permitted.

[zerog]

Thanks MichaelN,
yes i need only altitude, not speed, that's why i bought the Lassen IQ. So, if i don't exceed speed limit, the module will measure altitude also over 18000 m ? No configuration is required? I want to be sure about that, because i can't test it before the balloon launch Datasheet just says about the possibility to exceed the limit, but nothing about settings.

[MichaelN]

So, if i don't exceed speed limit, the module will measure altitude also over 18000 m ? No configuration is required?

That's what others seem to indicate. Google will reveal others' experience with these modules and balloons.

[zerog]

I found a lot of HAB teams who used Lassen IQ, i'll try to contact them....thanks!