That test flight was bogus. Your installer probably didn't have a clue, and
the FAA for SURE didn't.

Karl


"Ross Richardson" wrote in message
...
Oh, but my KLN-89/B was flight tested by the FAA and installer. It has to
be right. I have Dual MK-12Ds.

karl gruber wrote:

The main difference between a KX-155 and a KX-155A is that the later was
designed and built after GPS was in use. The "A" models do not interfere
with GPS.

ALL the older radios, straight 155, 170 series will interfere with GPS.
That is the reason one has to test certain frequencies in an IFR GPS
installation. One can be sure that if there is a straight 155,or 170 and
older radio in your airplane, you will not be able to pass that test.
Those who have, have "parker penned" the installation, regardless of how
many 'notch" filters have been installed.......that's just pure BS.

Best,
Karl
"Curator"


"Ross Richardson" wrote in message
...

This is a known problem with Com transmitters and GPS receivers,
especially with the older units. If I remember it is something like the
10th or 11th harmonic of the COM that can interfer with the GPS. I first
noticed it with my old Appolo 2001 that on certain transmit frequencies
the GPS would blank out. I contacted the manufacturer and they provided
me a paper which included something like 20 frequencies in the aircraft
band that could cause this. I check them and sure enough some did and
others did not. Also it is/was how close the two antennas are.

Ross

Jonathan Goodish wrote:


In article . net,
Mike Spera wrote:


I never did check the SW level of the old unit. I missed that one bit
of data. I will try the new one and check the SW level. If it performs
like the old one, I will upgrade and try again. If it still does not
work after the upgrade, I'll give Garmin a call before taking the unit
back for a refund.



I'm sorry to say, it sounds like you have an EMI issue. If you key the
mic and the sats drop, that's a pretty good indication of at least one
problem.

Upgrading the software to the latest code should go without saying.
Garmin will insist that you do that before they will help you
troubleshoot such an issue. Garmin did make GPS reception improvements
in some later software releases.



JKG