[aprssig] Re: GPS/PC/D7A

[Jason D. Triolo]

Alex Carver wrote:
> Hi Jason,
> 
> Just split the serial cable between the computer and
> the D7.  I do this very thing with my setup.  I have
> Street Atlas 2007 on my iPAQ and built a Y-cable to go
> between the single GPS receiver and the D7/D700 plus
> handheld.  Street Atlas doesn't need to communicate
> back to the GPS receiver so just leave that signal
> line disconnected between them.  Two signals (transmit
> and receive) between the radio and the GPS receiver
> and one signal from the GPS receiver to the computer.

A follow-up to this thread:

I went with the split serial cable option, and all that I wanted to do, 
is working. The GPS output is being picked up by the D7A, which I can 
leave in APRS mode. The PC is also receiving the data for Street Atlas 
'07 at the same time. As an added bonus, I was able maintain the data 
stream from the D7A back to the GPS, so that local stations get plotted 
on the handheld GPS unit's map. So if I can't get the stations plotted 
on my PC with my current software, I'll take the compromise.

My approach was to first get the connection working properly between the 
GPS and the D7A. Once that was done, I simply "tapped-in" a 3/32" jack 
on a short lead, and soldered it all together. When I need the computer 
connection, I can just use the same DB9-to-3/32" cable that I already 
own for programming and TNC-mode operations, and plug in to that socket. 
Either way, the D7A and GPS unit still talk to each other.

The finished assembly is much more compact than I first pictured in my 
mind, and is easy to stow away for future needs, when I can't make use 
of my mounted D700/Trimble system in my own car.

Thanks to all for the suggestions. KD4ACG-7 is now road-ready :)

73 de Jason, KD4ACG
www.fieldcomm.org/aprs