RG 174 cable with SMB female connector to USB

**stewrockka2** · 04-27-2005, 05:32 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, 06:43 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, 08:21 AM

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

**kiltjim** · 04-28-2005, 10:56 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, 05:54 PM

Thanks for the information.

Where can I go abouts and buy this receiver?

**jcdillin** · 04-28-2005, 06:11 PM

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

**Scouse Monkey** · 04-28-2005, 06:17 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, 06:20 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, 06:20 PM

DR all the way

**Scouse Monkey** · 04-28-2005, 06:23 PM

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!