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FlightBox ads-b to GRT EFIS

Tankerpilot75

Well Known Member
I am thinking about porting FlightBox ads-b "In" and weather data to my dual GRT Horizon WS EFIS system. I have already updated my FlightBox SIM card and purchased a FlightBox USB to serial data adapter.

My current system has the GRT weather module connected to the bottom EFIS's #2 serial port and had a Barron WX module on top of the GRT module but I removed that because it couldn't feed both the EFIS and broadcast iPad data at the same time. I also suspended my XM weather account due to its cost and the annoying need to "pin" the system if I went a few weeks without using it.

My questions are:
1. Has anyone in the VAF network connected their FlightBox (stratux) to their GRT EFIS?
2. If so, are their any gotcha's I need to be aware of?
3. The GRT instructions indicate the "stratux" needs to be connected to a "high speed" serial port but the FlightBox blog indicate the system defaults to a 38,400 baud rate. I'm not real smart about this stuff but I think this is a low speed baud rate. If I need to connect to a high speed baud rate port then that means using the #2 serial port my old XM weather unit was using and not an unused low speed serial port currently available. If you have done this I would appreciate some insight.
4. Where did you mount your FlightBox? Are you using a remote antenna?
5. Are you satisfied with the results?
 
I am using a Stratux that is connected to my GRT Sport SX and have been pretty happy with. I am not sure about the serial port issue as the Sport SX is a bit different setup, however it would seem easy enough to wire yours to the pin that had been used by XM.

Other comments:

I use the little telescoping metal antenna that came with the receiver for the Stratux box, velcro'd to the top of the glare shield. No problems picking up towers from about 1000' and above.

I have not been super impressed with the GRT's handling of traffic, as no matter how I changed the settings, I was getting audible 'traffic alerts' for ALL targets, no just those within a certain range. I ended up turning off all traffic alerts. Have not tried with the most recent software version, however, and I do have different software than your unit. I didn't install this for the traffic capability, so I consider this a minor inconvenience.

The weather information is great to have. I can color airports on the EFIS based on flight conditions, look up destination weather on the airport info screen, and of course see the radar overlay.

All in all, well worth the time to build and install.

Chris
 
Hi Jim,

I have been using Stratux on my GRT Sport HS EFIS since last April. I connected it to the same port my old GRT XM processor was attached to (in my case serial port 4, the high speed port on my second GRT or MFD display). I set the speed for that port in the EFIS to 38400 baud.

I did all this with an old version of Stratux software (0.8), the one mentioned in the Stratux supplement on the GRT website. My understanding is that FlightBox and Stratux both now support serial interface still at 38400 baud. You just need to connect the RS232 OUT from FlightBox(using their USB to serial adapter) to the RS232 IN on your GRT and then follow the instructions in the GRT supplement.

The weather works great, just like XM used to. I see traffic but I'm not real confident in it. I'll have a better idea after I install my Appareo ESG for ADSB OUT.

I do not see the number of towers that the supplement shows and the age of radar image doesn't work correctly. Jeff at GRT says if I had a GPS in my Stratux that would solve that problem (GRT needs time info that GPS will supply). I plan to add the Flight Box AHRS module to have a back up attitude indicator and that module has GPS so hopefully that will fix these problems.

Jim Butcher
 
The GRT Stratux instructions are pretty specific that only high speed ports will work.

Traffic alerts: there should be an altitude filter set up on the main menu, e.g., set for plus or minus 3000 vertical feet. On the map page, turn down the range. I don't think there are alerts for traffic that is off-screen.
 
I have a Stratux connected to my GRT HXr and it works well for me (Traffic & Wx). The latest version of Stratux allows serial output via it's USB port. You can get a USB to serial converter and integrate that way. I used an adapter that converts the USB to TTL level RS-232. I have another adapter that converts the TTL back to USB connected to the GRT. That helped me conserve serial ports. There are two primary USB->serial chips out there. One works well on the GRT and the other doesn't (no driver support). See my post on Github if you want details. It was the FTxxxx chip that work.

In case it was your next question, you cannot directly connect the two USB ports, as they are both Hosts.

I don't have a flightbox, I rolled my own Stratux.

PS you can change the baud rate on the stratux if trying to use a slow speed port on the GRT. You can do this with the Web UI tool for stratux. Be sure to close the Web UI tool before turning off the Stratux or your changes will not be saved.

Larry
 
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The GRT Stratux instructions are pretty specific that only high speed ports will work.

Those instructions are old and out of date. You can find better support on the Stratux area of Github. For example, changeable baud rates have been introduced since then. Also, the version on the GRT site is very old.

Larry
 
Need schematic of GRT Horizon pin layout

Does anyone have a schematic of the Horizon d-sub pin connections that plugs into the back of the EFIS unit? My bottom EFIS MFD has two wires running from my old GRT weather module to the bottom d-sub pin connector (male connector on wire side/female on EFIS side). The blue wire connects to the #4 d-sub pin and a white wire connects to the #17 d-sub pin. Since my general settings indicate the weather module is connected to serial port #2, I assume these two pins are for serial port two. Unfortunately I cannot tell which one is an "input."

If anyone has a pin description for the two d-sub pin connections on the back of the GRT Horizon EFIS I would appreciate a copy. I cannot find one on the GRT documentation website.
 
Does anyone have a schematic of the Horizon d-sub pin connections that plugs into the back of the EFIS unit? My bottom EFIS MFD has two wires running from my old GRT weather module to the bottom d-sub pin connector (male connector on wire side/female on EFIS side). The blue wire connects to the #4 d-sub pin and a white wire connects to the #17 d-sub pin. Since my general settings indicate the weather module is connected to serial port #2, I assume these two pins are for serial port two. Unfortunately I cannot tell which one is an "input."

If anyone has a pin description for the two d-sub pin connections on the back of the GRT Horizon EFIS I would appreciate a copy. I cannot find one on the GRT documentation website.

All the manuals I have seen on the GRT site have detailed pin outs for the units. Look a bit harder.
 
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