InterceptRadio.com Forums

Quick question. I have one of those cheap GPS receivers that was bundled with Delormie Street Atlas. The GPS is USB. I have searched and searched for a USB to serial adaptor with no luck (it seems no matter how you type it you always get a serial to usb adaptor)
anyone know if such a thing exists?

Also in my readings on the net, I can bring a computer into the mix and plot/see other APRS users. Does the Kenwood 700a have a serial in and out? How does the radio and pc use the gps at the same time?

Annnd will that software work with the plotting process. I have seen a lot of software to use for APRS I'm just wondering if anything like MS streets or the software I bought will work.

Thanks for the help.

Hello Larry,

Which GPS unit do you have? Many have a seperate NMEA output that can be used. As for any specifics, we will need to know the make/model of all the equipment. This will determine your configuration. Even the software you select can make a difference.
For a list of good APRS contacts, go to the link below for Northwest APRS Elmers:
http://nwaprs.info/nwaprselmers.htm

73 de Michael

_________________
Thank You,

Michael
ARS - KG7HQ
Assistant Director/Technical Specialist/VE
Northwestern Division
ARRL
kg7hq@arrl.net
http://www.kg7hq.wetnet.net

After downloading the manual for the d700a, I see it has a 2.5mm 3 conductor jack for the gps. I have sent a few emails out to some GPS companies asking for specifics.

That solves the mystery on how it and the pc uses the gps. The serial db9 goes to the pc and 2.5mm goes to the gps.

Now I have to figure out how to make a usb turn into a 2.5mm jack/port.

I also have to figure out to power the gps since the 2.5mm jack isnt going to do that.

Hasn't someone come up with something by now?

As far as the gps model....I have to go get it out of my work van. Just picture the normal 3" by 3" black box with a 3' cable with a usb connector on the end. I do know its NMEA compliant.

Thanks again

Forget my last question. I'm going to have to buy a new gps...maybe

Here's my newest dilema:

SO I get a new gps (serial) and I connect that to the tnc. How do I connect a laptop???

Every radio I've seen has one serial port. If I don't buy a radio with a gps input (the kenwood d700a uses a 2.5mm plug and the Alinco 135 uses a 3.5mm plug) how can you put a latop or any pc to use with aprs. With that in mind why buy a gps with a serial port in the first place? niether one of those radios use the serial for the gps.

As you can see I am dead set on using a laptop so I can see other aprs users while on the road.

Please help.

Two ways.....

1. If using an older TNC (Kantronics KPC-3), you can use a HSP (I believe that stands for "hardware serial port"). It's essentially a "Y" adaptor that connects your GPS to a computer and a TNC simultaneously. A couple of transistors inside the "Y" adaptor will switch the GPS data stream between the two devices periodically, and allows both of them to work. The HSP can be either built or purchased.

Here's a link to some information, but I don't think the diagrams are working:

http://nwaprs.info/hsp.htm

2. The Kantronics KPC-3 PLUS does have two serial inputs - the normal 25 pin DB-9 connector is used to connect a computer to the TNC. The GPS data is fed into the GPS unit via the DE-9 connector (where the radio plugs in). That's how I'm using my PalmPilot in the vehicle - it works well, and I know others that use laptops in that configuration without problems.

Brad N7JGX
Whidbey Island, WA

_________________
Whatever.....

I do hope this solution will work. I just bought one for 149.99 and I dont have to cut up my own gps receiver....it comes with one!

http://cgi.ebay.com/Trimble-Crosscheck-XR-GPS-2-ports-NMEA-TSIP-TAIP-APRS_W0QQitemZ5821931420QQcategoryZ4671QQssPageNameZWDVWQQrdZ1QQcmdZViewItem