Hi All
My electrical knowledge is VERY basic so I have a question for all of you electrical avionics gurus.
I have a GARMIN 335 ADS-B which has been functioning perfectly since installation 11/2018. Recently I started receiving messages indicating "pressure altitude failure" which according to the troubleshooting guide suggests a loss of signal from the altitude encoder. The GARMIN receives pressure altitude info via the RS232 serial output wire from the harness of a DYNON D-100 which has a built-in altitude encoder. The pressure altitude will function for a few seconds and then drop out and then return and so on. I realize there are many sites that could be the culprit. My first thought was to ascertain that I was receiving a continuous signal from the serial RS232 out wire from the DYNON D-100.
I can easily access this wire where it connects to the GARMIN 335 RS232 serial input wire on the ADS-B harness. Is there a simple way to attach a meter of some sort to the RS232 output wire from the DYNON and check the signal?
Sorry for the long post.
Peter K
RV9A 800 hrs.
My electrical knowledge is VERY basic so I have a question for all of you electrical avionics gurus.
I have a GARMIN 335 ADS-B which has been functioning perfectly since installation 11/2018. Recently I started receiving messages indicating "pressure altitude failure" which according to the troubleshooting guide suggests a loss of signal from the altitude encoder. The GARMIN receives pressure altitude info via the RS232 serial output wire from the harness of a DYNON D-100 which has a built-in altitude encoder. The pressure altitude will function for a few seconds and then drop out and then return and so on. I realize there are many sites that could be the culprit. My first thought was to ascertain that I was receiving a continuous signal from the serial RS232 out wire from the DYNON D-100.
I can easily access this wire where it connects to the GARMIN 335 RS232 serial input wire on the ADS-B harness. Is there a simple way to attach a meter of some sort to the RS232 output wire from the DYNON and check the signal?
Sorry for the long post.
Peter K
RV9A 800 hrs.
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