GPS handheld input into tracker

Allen,

I bought the GPS unit from Byonics and it easily plugs into the tracker and is automatic, but now I don't want that extra "thing" to have to connect. I have a GPS III Pilot handheld Garmin GPS that already feeds NEMA to my autopilot and my Dynon Engine Monitor. If I want to use that data stream into the Micro Trak 300, do I just connect it to pin 3 and let the PIC decode it? Thanks in advance. I want to make the installation a permanent thing and this will make it the simplest.

Rick Grenwis

grenwis said:

Allen,

I bought the GPS unit from Byonics and it easily plugs into the tracker and is automatic, but now I don't want that extra "thing" to have to connect. I have a GPS III Pilot handheld Garmin GPS that already feeds NEMA to my autopilot and my Dynon Engine Monitor. If I want to use that data stream into the Micro Trak 300, do I just connect it to pin 3 and let the PIC decode it? Thanks in advance. I want to make the installation a permanent thing and this will make it the simplest.

Rick Grenwis

Click to expand...

Rick, I'm not Allen but I can answer your question because that is precisely how I feed GPS data to my tracker (I use a Garmin GPS35 hockey puck receiver). Connect the NMEA stream to pin 3 and also connect a signal ground on pin 5 if the tracker and GPS are not grounded to the airframe. The Micro-Trak 300 includes the Tiny Trak decoder that is needed to send the data to the transmitter.

You may run into problems if the data signal out of the GPS isn't strong enough to feed three devices, but you won't damage anything by giving it a try.

Thanks Sam

Thanks Sam,
I was glad when the GPS could also drive the Dynon EMS I just put it, but now I guess I'll push my luck and try a third. Thanks for the quick reply. Tomorrow is supposed to be a nice day here in Denver so I think I'll make the mods and try a quick flight. Without the GPS puck on the glare shield, I won't have that cable routing around the corner to the radio that will be behind the panel. What a fun toy this is!!
Rick Grenwis
RV6A

grenwis said:

Thanks Sam,
I was glad when the GPS could also drive the Dynon EMS I just put it, but now I guess I'll push my luck and try a third. Thanks for the quick reply. Tomorrow is supposed to be a nice day here in Denver so I think I'll make the mods and try a quick flight. Without the GPS puck on the glare shield, I won't have that cable routing around the corner to the radio that will be behind the panel. What a fun toy this is!!
Rick Grenwis
RV6A

Click to expand...

Rick, if you end up having to use the little GPS, you might consider mounting it under the cowl, clamped to one of the upper engine mount tubes. You will need a hole in the firewall large enough to pass the D-sub, but it can be easily resealed with a small cover made from scrap stainless. Or, you could remove the D-sub so you can use a really small hole and reattach it after the cable is run.

I have the GPS35 receiver and external antenna for the Airmap on the glareshield with the leads running through a grommet and down behind the panel. That would be another option for you if you need the GPS.

Either way, you'll end up with a nice APRS rig. Not only is APRS a cool thing to work with and reassuring for your family, it is just a matter of time until someone demonstrates how valuable it can be when really needed. We'll be watching for your flight.

Various GPS receivers

Most GPS receivers that produce NEMA data output, either TTL or true serial, have sufficient "fan out", or drive levels, to run multiple devices. If the green LED lights and stays on, the level is good!

Allen

Does anyone have any information on noise regarding the PS-8000? I thought they had auto sqelch.

Yesterday I tried connecting the NEMA from my handheld into pin 3 on the tracker without success. I didn't connect the ground and that easily could have done it. When I have more time, I'll try a more rigorous test and see if it works. Since I'm driving 3 things, I can imagine a closer ground might be needed to reduce noise.
Rick Grenwis

OOPS

grenwis said:

Yesterday I tried connecting the NEMA from my handheld into pin 3 on the tracker without success. I didn't connect the ground and that easily could have done it. When I have more time, I'll try a more rigorous test and see if it works. Since I'm driving 3 things, I can imagine a closer ground might be needed to reduce noise.
Rick Grenwis

Click to expand...

Rick, try pin 2, that is the serial "in" pin.