In Europe there isn’t the US Experimental option for avionics testing in a certified aircraft…
You can install anything you like as “removable equipment”. Just fix the box with velcro to the top of your cowling or a side panel and connect the wires with plugs and you will be fine – even in Europe (this is how 95% of all electronic flight bags, be it iPads or notebook computers, are operated legally in aircraft of all sizes).
Garmin does seem to do a bit better. They introdoced 8.33 radios as standard (on their GNS430s) in 1998!.
Garmin poorly implemented 8.33 in their early GNS430 / 530. Check EASA SIB 2008-58R1
In April, when flying Brest aerea ir, we had to use 8,33 khz. So it is in active use.
Reminds me that during an IFR flight last week in the Paris area I overheard a conversation between ATC and a government aircraft which obviously did not have 8.33 radios and was asking if Brest had UHF 
What about that?
i got 2 kx 155
my question is if i have to go for 8,33, if i could install a stand alone 8,33 radio (garmin or trig) and than dissconnect com 1 (the com side of one of the kx155) and use in that place the 8,33 stand alone
i also have a kma 24 instaled and i am on N reg
any suggestins
I am trying to find a very economic way for 8,33 VFR only
That could be done. Or maybe you could give it some more time, and wait an see when their is more equipment available. Do you need 8,33 kHz now? Trig will have “flat” radio at the end of the year. There are radio’s out their which have a lower pricing, though I have had quite some qualitity issues with them. From Trig and Garmin, Trig would give you the most economical solution of the two, and Trig dealer support is amongst the best around, so your dealer would be able to give you good support as well should anything go wrong. I did have issues with all brands, for sure Trig has produced the least issues for me.
thanks Jesse as always great info no i am not in a hury what do u mean with “flat” radio?
Trig would bealso my first choise
One that fits in a normal radio stack – all the current Trig units are small units.
After I saw the Trig based Bendix King KT74 transponder which is a nice unit at a good price (and has a better user interface than the actual Trig model), I had hoped there may soon follow a similar 8.33 radio.
Why not just slide a KX165A into the rack and be done with it ?
If you have a 12V aircraft a few minor changes in the wiring to put in a voltage converter are required but if you get this done at the annual check the labour costs can be kept down as a lot of the paneling will be removed for the annual inspection.
The new EASA CS-STAN regulations make this an attractive option for those not on the N reg as it cuts down the paperwork that was required by the old system.
Well, the KX165A is mighty expensive, you almost get a good GNS430 for that amount of money – and then you’d have a good GPS, too.
I would either do as Pater Paul desribed, if there is space availiable for a small Trig and just keep the com wired to any other input in the KMA24, some port I now don’t use. TEL for instance. This way it would be okay for tuning in ATIS or local frequencies for monitoring only (provided you have enough antennas). I have even seen installations with a fixed PTT and Mic Input “Emergency Use Only” hardwired to the unit.
