RG 174 cable with SMB female connector to USB

stewrockka2 · 04-27-2005, 06:32 PM

My work deals with GPS tracking units which are installed in vehicles, but I had to the idea to connect a USB connector to one of the GPS antennas so that I can hook it up to my laptop and use Streets & Trips.

The connector on the GPS antenna right now is a SMB female and I want to convert it to a USB. Is this possible? Would I need any firmware/software, etc? (new to this stuff)

I know that USB has +5v, D+, D-, GND...so we figured that +5 on the USB will go to the antenna supply, connect D+ with a capacitor to ground, then D- with a capacitor to 5v, and GND on USB to GND on the antenna.

I also scanned the instruction sheet for the antenna if it has any other useful information. Thank you very much!

DJSmiley · 04-28-2005, 07:43 AM

You can't.

This antenna is only an active antenna. (power supply needed for the active part).

You WILL need a receiver in order to use it. Most current receivers are based on the Sirfstar II chipset, like e.g. the BU-303. Older ones are based on e.g. Rockwell chipsets.
This receiver converts the (1.3Ghz if i'm right) signal into a RS232 compatible signal. (With a MAX232 or something simular to make the levels PC-serial compatible).

Additional, a USB->Serial convertor might be included, mostly based on the Profilic chipset. Usefull for pc's without serial

Anyway: get a GPS receiver. I have a BU-303 and replaced its internal antenna with an external (waterproof) one, just like the one you have. But without additional electronics, its useless.

pate60 · 04-28-2005, 09:21 AM

im only it were that simple, then GPS would only cost $20!

kiltjim · 04-28-2005, 11:56 AM

DJSmiley is right. From what you are saying, you only have an antenna. You still need a reciever to convert all the data from whats coming off of the antenna.

stewrockka2 · 04-28-2005, 06:54 PM

Thanks for the information.

Where can I go abouts and buy this receiver?

jcdillin · 04-28-2005, 07:11 PM

depends on which one you want, garmin, ublox, trimble the list goes on.

Scouse Monkey · 04-28-2005, 07:17 PM

RF solutions do some nice OEM GPS modules for abotu £33.

But some require a bit of work to add serial or USB conenctions. I think RF solutions fo serial and USB ready one s that look quite good from their specs. Should be better than most USB mouse type GPS solutions,.

Or you can wait until jcdillin and I do the dead reckoning GPS system - that is gonna rock!

stewrockka2 · 04-28-2005, 07:20 PM

Well, this isn't really needed, just wanted as I have a laptop I don't really use so I thought it would be neat to hook up GPS to it. We also deal with GPS units at work, so I most likely can order one up and get it for a half decent price. I will look into it tomorrow.

jcdillin · 04-28-2005, 07:20 PM

DR all the way

Scouse Monkey · 04-28-2005, 07:23 PM

Quote: Originally Posted by jcdillin

DR all the way

hell yeah!!

you can build an oem type system with separate antenna for a about £33 (module) and £14 (antenna). That works out cheaper than a BU-303!!!

but quite frankly, DR is where it's at!

stewrockka2 · 04-28-2005, 07:32 PM

Quote: Originally Posted by Scouse Monkey

hell yeah!!

you can build an oem type system with separate antenna for a about £33 (module) and £14 (antenna). That works out cheaper than a BU-303!!!

but quite frankly, DR is where it's at!

And how would I go about building this OEM type system? Any links to websites or anything? I can get the antenna no problem...

jcdillin · 04-28-2005, 07:34 PM

http://www.ublox.com

http://www.u-blox.com/products/sbr_ls.html

Scouse Monkey · 04-28-2005, 07:38 PM

Quote: Originally Posted by stewrockka2

And how would I go about building this OEM type system? Any links to websites or anything? I can get the antenna no problem...

have you

ed?????

you can find some info on this forum (search for OEM modules)

if you re-read my previous post i did say you may need to make USB or serial interfaces (i prefer serial) or RF solutions may do a ready made unit for cheap.

i onyl started looking at GPS systems 2 days ago and I am already working on a dead reckoning system - it's not hard to learn. But you need to read. Start with the OEM GPS threads on here and then go look at some hardware on manufacturers sites. I can't be much help i am afraid as I am new to it and might advise you wrong. I am jumping strraight into the deep end as no one on here has done a DR system before. it has been discussed but not done. Even my avionics lecturers at work were amazed it could be done so easy when i asked them for advice.

Scouse Monkey · 04-28-2005, 07:40 PM

Quote: Originally Posted by jcdillin

http://www.ublox.com

http://www.u-blox.com/products/sbr_ls.html

Those are were we are looking but if you are not very confident with electronics and want soemthign cheap and easy then look for a system with the outputs on and the battery backup already one.