The International Cessna^® 170 Association

Folks, I'm going to install a garmin 300xl with a Collins ind 350a CDI which won't be shared with a vor. I know. To be tso'd I need to include a annunciator. I have seen a MD41-1444 and a MD41-444. I know the 444 is used when sharing the CDI with a vor. Since I'm not sharing the gps with a vor is the 1444 all that is needed? Just want to confirm before the radio guy gets involved. I saw a blurb where there might need to be a relay installed but I'm not sure that applies to a CDI that is gps ready like the Collins. Does anyone know?
Thks

Ok, first you have the wrong term. TSO means Technical Standard Orders. It has nothing to do with whether or not you have an annunciator panel installed. What I think you are confusing it with is what requirements you would have to have installed in order to have the installation certified for IFR.

If you do not want to have an IFR certified installation, you do not need an annunciator panel. All it is really is an electronic switching device that is capable of switching what drives a CDI, the VOR or GPS. It also has switches that operate the GPS. And of course it has lighted indicators to alert the pilot what is chosen and or when a switch can be or should be activated. For example there will be a hold switch and an approach activation switch. Many of these things can be done at the GPS but not necessarily all of them in the earlier GPS units. Also in the early days with GPS mounted in the center console between pilots the installation didn't meet the expectations of the FAA of having such indications in the scan of the pilot. So the annunciator panel was born.

Today, since the 430, if the GPS is in the instrument panel, in the view of the pilot, the annunciation and switching is built into the GPS and no further system is required.

But of course you are installing a 300xl. It's been many years since I've looked at the requirements and specific GPS units but I seen to recall that you would need an annunciator panel for the 300xl for an IFR installation regardless if you where trying to drive your CDI with both a GPS and a VOR. If your just doing a VFR install, unless you can get the annunciator for cheap, forget it. But to be honest if your not doing a IFR install why are you even installing a CDI?

Collins 351 with except left-right direction from a GPS directly. It is the CDI I used.

As Aryana pointed out the GPS must have the annunciator built in AND it must be within a given angle of view from the pilot to be installed without an additional annunciator panel and be certified for IFR. If the GPS doesn't doesn't have the annunciator functions built in or the GPS is located out of the allowed angle, then an additional annunciator panel located within the allowed angle is required as well as a right-left indicator (A CDI which technically is not a CDI when functioning with a GPS)