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While flying today my GRT crapped out! It blinked a couple times and then all the info went blank. After landing it says check entries. I plan to take Manuel to airport tomorrow and see if there anything I can do before calling GRT on Monday. If anyone had this happen to them and know how to fix send me a message.

Hey Brent.
Sorry about the GRT .I'm sure it will be an easy fix.
I have been thinking of going with the GRT 4000 for my Onex.How do you like it overall ?Easy to set up? Would you recommend it ?
Thanks,
Mike

I have the Grand Rapids 4000 EIS with the Sonex fuel probe, altimeter, and airspeed indicator, 3 years on my Sonex/Aerovee. It was easy to set up, and has performed perfectly. My only other instruments are the Ifly moving map GPS and the Flightline 760 radio. I would rcommend all of them (the radio needed internal adjustments).
Bill

Thanks for the input Bill.I have had an Ifly since it first came out and plan on putting the smaller 520 in my Onex.Great GPS.

GRT called me today and said they found no problem with engine monitor and the problem sounds like a voltage spike. I plan to check connection and monitor buss voltage with a meter to see what's going on. Any one seen this problem?

First let me explain that I am 80! I have the above with altimeter, etc. and have never been able to use it correctly. When I push the ptt the light comes on. Altimeter is always wrong. Have never been able to check the mags at 2,000 as it goes crazy, numbers all over the screen. On take off the light comes on then goes off.

Does anyone know anyone or a shop in NC VA or SC that could help me. I am located in central N C . Siler City, N C. My cell is 910-571-8313. I would be glad to pay for assistance.

Thanks

Larry Long

sonex1077 wrote:First let me explain that I am 80! I have the above with altimeter, etc. and have never been able to use it correctly. When I push the ptt the light comes on. Altimeter is always wrong. Have never been able to check the mags at 2,000 as it goes crazy, numbers all over the screen. On take off the light comes on then goes off.

Larry,

I had a similar problem with my EIS that turned out to be stray RF energy from my comm radio reflected back into the various sensor wires of the EIS. The symptoms were similar to what you describe: PTT causes all sort of erratic numbers of the screen, random fluctuations in certain readings for no apparent reason. The solution for me was two-fold. 1) ensure the COMM antenna routing is well clear of any EIS power or sensor cables. 2) I added clamp-on ferrite beads to the sensor and antenna wires to trap and eliminate any stray RF energy from getting into the EIS. My website has the full description and part suppliers I used.

http://sonex604.com/eis_interference.html

The rest might just be some setup issues. There is a way to adjust the EIS altimeter to calibrate it to ground level. The light coming on from the PTT is likely due to the stray RF energy tripping an alarm point and nothing more. The mags might be something from the alternator output that's messing with the EIS. Perhaps a 2k-ohm resistor in-line of the tack signal wire will quiet that down some (just a thought?). That could also be a result of the kill wires to the mags turning into long antenna wires when one of them is grounded out (during the mag check) and sending RF into the EIS as well. You can check this my examining the kill wire routing, and even make up some new temporary ones that are routed differently to see if that helps.

Jeff