Shop OBEX P1 Docs P2 Docs Learn Events
Constant Navigation with GPS Questions — Parallax Forums

Constant Navigation with GPS Questions

John AbshierJohn Abshier Posts: 1,116
edited 2013-10-02 09:46 in Accessories
1. Why did you power the GPS with 5 volts? Product page says 3.5-5 volts.

2. What is the purpose/requirement for the emitter/follower circuit?

John Abshier

Comments

  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2013-10-01 13:58
    John, I'm missing some context here. Was this post supposed to go into a different thread?

    -Phil
  • John AbshierJohn Abshier Posts: 1,116
    edited 2013-10-01 14:22
    I just saw the link to Constant Navigation with GPS on the Parallax site and read it. I would have used 3.3 volts since it is a Propeller project and just wired RX-TX/TX-RX, possibly with 220 ohm "safety" resistors.

    John Abshier
  • Nick ErnstNick Ernst Posts: 138
    edited 2013-10-02 08:54
    John,
    - I powered the GPS module with 5v because I have used this GPS in many different projects and applications and have had better results with it powered off of 5v than I have had with 3.3v. I have seen better satellite tracking and acquisition with a 5v source.
    - The purpose of the emitter/follower circuit is to allow you to re-configure the GPS module to be in "Constant Navigation" mode. These modules have to be internally re-configured to change between modes.
    - You can use a 3.3v source for your GPS, but like I mentioned, I used a 5v source because I have seen better results in my applications.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2013-10-02 09:12
    Here's further explanation of the reason behind the emitter follower circuit:

    -Phil
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2013-10-02 09:13
    I can confirm that the Polstar modules definitely perform better when run from 5V, even though the manufacturer specifies 3.3V or 5V operation.
  • John AbshierJohn Abshier Posts: 1,116
    edited 2013-10-02 09:46
    Thanks everyone.

    John Abshier
Sign In or Register to comment.