HI... I am using the Fastrax 530 in periodic mode eith 2 sec ON and 15 sec OFF.

[jorge rodriguez]

HI.. I am using Fastrax 530 in power periodic mode with profile 2 sec ON by 12 sec OFF to save energy. I managed to get fix in that time but the deviation is enourmous (about 300 metres after one hour). Looks to me that the problem is I am not geting sufficient ephemeresis data in such short time. I need to know what would be the minimum time ON to get better performance.

 

[Nuvi-Nebie]

Are you maintaining backup power to pin 2?, without this all stored data will be lost

 

[jorge rodriguez]

Dear Sir... Thanks once agin for your quick response. Let me elaborate even more my problem. The receiv er is the FastTrax530 and before strat the test, I am in continue mode in order to be sure the receiver have a full ephemeris. I am not switching Off the VDD nor the battery VDD_B any time physically. I am sending a periodic mode command. $PMTK225,1,3000,12000,18000,72000*16.... and the receiver start to operate 3 sec ON by 12 sec OFF. I get fix 3D in 2 sec... no problems. But the deviation map start to show great dispersion of data up to 300 m!!!. The baud rate is set to 9600bps and it is not the problem.... the great problem is the dispersion of position over the time. Looks that you did not mension what is the minium time ON in order to get the ephemeris alive. Let me see if I am more clear... maybe I did not undertood your idea. Nice day...JORGE (Pretoria)

 

[Nuvi-Nebie]

Hi Jorge, I don't have a Fastrax 530 module, I only have the data sheet, it does say that you will get reduced fix rate / accuracy when in periodic mode, have you tried 'Alwayslocate' mode?, this claims to maintain a good fix when in periodic mode by automatically varying the 'on / off' periods. If this does not work for you I guess you will have to keep extending the 'on' period until you get the accuracy you are looking for

 

[jorge rodriguez]

Dear Nuvi-Nebie.... I agree with you... I am testing many times ON/OFF to see which is the best. In any case I will try also 'Alwayslocate' mode' ... may be works better. haa...thanks to be there... you are magnificent!!!!....Jorge in Mandelandia