Tommycat
Active Member
Hiyas Steve with Garmin! Thanks for the reply.
So are you saying that anyone with a Bose A20 ANR headset walking around the perimeter of their aircraft on battery power will pick up this noise? Has this been your experience?
This is a quote from the instruction manual page A-1...
"If replacing a GMA 240 with a GMA 245, the GMA 240 (330-00220-25) connector backshells can be reused. However, grounding the wire shields to the GMA will be easier with the Garmin backshells in GPN 011-02302-00. The Garmin backshells also offer higher immunity to HIRF. Current installations will not be required to change the backshell type, but would benefit from doing so."
If the benefit in higher immunity to HIRF was good enough, wouldn't this be a preferable choice? This is why I ask if this has been tried.
Reading it a few times more... is current installations referring to a non-Garmin install? So perhaps both backshells offer the same degree of immunity? Please clarify.
Best Regards,
It does not, however, stop an ANR headset from picking up noise if it is prone to do that.
So are you saying that anyone with a Bose A20 ANR headset walking around the perimeter of their aircraft on battery power will pick up this noise? Has this been your experience?
When I installed the GMA 245 into the GMA 240/340 rack, I did not change out the connector backshells to the new style as that was not necessary to eliminate the issue. With proper cable shielding and termination, the new metal backshells do not significantly change the installation.
This is a quote from the instruction manual page A-1...
"If replacing a GMA 240 with a GMA 245, the GMA 240 (330-00220-25) connector backshells can be reused. However, grounding the wire shields to the GMA will be easier with the Garmin backshells in GPN 011-02302-00. The Garmin backshells also offer higher immunity to HIRF. Current installations will not be required to change the backshell type, but would benefit from doing so."
If the benefit in higher immunity to HIRF was good enough, wouldn't this be a preferable choice? This is why I ask if this has been tried.
Reading it a few times more... is current installations referring to a non-Garmin install? So perhaps both backshells offer the same degree of immunity? Please clarify.
Best Regards,
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