TSO

I agree with Edd and Josef. If non-tso'd stuff weren't legal to install, how could the avionics manufacturers get away with making it in the first place? The logic of it, which may or may not apply when dealing with FAA, is that TSO'd stuff is built to a higher standard and fulfills certain testing and engineering criteria such as vibration and moisture tolerance, minimum output power, and esp with transceivers, frequency accuracy since the TSO'd units go into corporate and Part 121 planes that fly at higher altitudes where there is more chance of overlapping frequencies interfering with others' radios at longer distances. I think there's a reg that says you can't climb into the flight levels (above 18000 msl) with non-TSO'd radios.

Chris

P.S. Just for fun call your FSDO back and ask them to show you in where the regulation is that supports them saying you need the TSO.

Kevin

It is a waste of time anymore to call a FISDO about our CAR certified aircraft. What little they know is only about FAR aircraft. I remember a time when you could call and get a straight answer you could believe but sadly those days are long gone.

Kevin

Thanks!

George: I concur with the non TSO - Thousands and thousands of King KX 170 series nav/coms (non TSO) were installed only the KX175 was/is TSO. I think some of the issue has to do with IFR rated.
But to solve the situation, check out the Sigtronics SPA400, IIRC the model #. Have one in my Coupe and wanted to replace the name plate, it's panel mounted - contacted Sigtronics and they sent me new plate gratis - plate is reversible to allow vertical or horizontal mounting of unit- small, compact, comes with good instructions, etc.Face plate is plainly marked TSO. Reasonable priced. Obviously pleased with performance.

Edd