Sparkfun Venus GPS - with support for 10Hz update rate

**ptk** · 08-10-2009, 08:14 AM

I remember someone asking for GPS hardware with faster than 1Hz update rate.

I was recently doing my new CarPC and was playing with GPS modules from Sparkfun.

I am playing with the Venus GPS with SMA connector

Features:
* 51 channel acquisition and 14 channel tracking
* SkyTraq based chipset
* 10Hz max update rate (1Hz default)
* Integrated LNA
* Single 2.7-3.3V supply
* 3.3V TTL UART
* Power: 28mA tracking
* Sensitivity: -161dBm
* Accuracy: <2.5m
* Hot start: 1 Seconds
* Cold Start: 29 Seconds
* Supports active or passive antennas
* Supports SBAS (WAAS, EGNOS, MSAS)

The features in bold above stands out rather well. Having said that, this module talks in SPI or TTL, so you will need to interface to your system appropriately.

Also for those who wants to keep the GPS running, 28mA power requirement will be ideal.

**DarquePervert** · 08-10-2009, 02:00 PM

But does it output NMEA sentences for popular GPS navigation software packages?

**Sicarius** · 08-11-2009, 12:02 AM

From the datasheet at the link above:

Protocol NMEA-0183 V3.01, GGA, GLL, GSA, GSV, RMC, VTG (default GGA, GSA, GSV, RMC, VTG)
SkyTraq Binary

**ptk** · 08-11-2009, 01:19 AM

Originally Posted by Sicarius

From the datasheet at the link above:

but honestly, can't imagine any chipset not supporting NMEA

**millsy** · 08-11-2009, 07:27 AM

This might be of interest to those seeking higher than the standard 1 hz update rates,also is just plain interesting.

http://www.gpspassion.com/forumsen/t...TOPIC_ID=76813

**ptk** · 08-14-2009, 03:43 PM

finally got all my bits in.
the original board comes with card edge SMA. Brought in some RP-SMA edge bulkhead as all my RF connectors are RP-SMAs.

Desoldering the original card edge connector is very tricky as there are SMD components near by. I dremeled off the connector before de-soldered off the legs. Soldering on the new connector is fairly straight forward.

I use a Sparkfun Breakout Board for CP2102 mini USB to Serial to interface to the GPS board. This is a good choice in view of its compact size as well as availability of 3.3V power supply. I also ran a line from motherboard's on board disc battery holder to supply the GPS board to supply the SRAM (this will shorten your warm start time).

Both boards are shrinkwrapped after the wiring.

Tested the GPS with Skytraq's own GPSViewer software. It's clocking fantastic cold start time of between 21-30 sec while testing indoor. There is a fair bit of drift of between 2-4m while testing indoor. Will run further testing once i get the car pc back to the car.

**Sicarius** · 08-15-2009, 11:06 PM

Nice job of replacing the connector and all but I can't say I'm a big fan of hanging a board from soldered connections on a PCB especially in a vibration prone environment like a car. How come you didn't just get an SMA to RP-SMA pigtail so you could mount the GPS board on a more stable surface?

**ptk** · 08-15-2009, 11:15 PM

Originally Posted by Sicarius

Nice job of replacing the connector and all but I can't say I'm a big fan of hanging a board from soldered connections on a PCB especially in a vibration prone environment like a car. How come you didn't just get an SMA to RP-SMA pigtail so you could mount the GPS board on a more stable surface?

Sicarius. I did that with previous project. But this particular board is so small, i figure it's light enough to hang off the connector. further more, the board is so small, it's actually difficult to mount properly.

**Sicarius** · 08-16-2009, 12:03 AM

Well, as for mounting it, I figured some Velcro would handle that nicely.

**Parakie** · 11-21-2009, 07:47 PM

I'm looking to implement something similar for my build, as I was searching for a 5/10hz usb receiver that supports an external antenna. The CP2102 board is now out of stock, and apparently you can use BOB-00718 sku as the replacement. Is it just the rx, tx, 3.3v, and ground lines that need to be connected?

Has anyone else done this? How well does it work a few months in?