This is one US seller. GTX330 for peanuts. Does Part-ML allow the installation of a transponder, with this concession?
Based on my experience of buying used gear from the US, some of these will be dud…
But what is the European list price of a GTX330?
GTX330 without Form 1 can be had in Europe for €800-900, but these are plain 330 without extended squitter, 330ES command a lot higher price. A Form 1 will be, say, another €150. If you just need a basic mode S transponder, it’s an excellent choice – good ergonomics and good functionality. One thing to check is whether the deal also includes the rack!
Note that an upgrade from an old mode C transponder may also require a new encoder if the old one only supports 100-ft resolution.
Ultranomad wrote:
Note that an upgrade from an old mode C transponder may also require a new encoder if the old one only supports 100-ft resolution.
There is, AFAIK, no requirement for a 25 ft encoder with mode S. Certainly we have aircraft with mode S and 100 ft encoders. (Slide-in replacement of old mode C transponder.)
Airborne_Again wrote:
There is, AFAIK, no requirement for a 25 ft encoder with mode S.
There is no absolute requirement indeed, but AMC1 ACNS.D.ELS.025 recommends against Gray code encoders. Also, as the altitude reporting error should not exceed 125 ft, having an encoder with a resolution of 100 ft effectively reduces the possible hardware error margin.
Ultranomad wrote:
AMC1 ACNS.D.ELS.025 recommends against Gray code encoders
It stretching it to say that it recommends against them. It does recommend against installing such encoders, but I can’t see that anyone would want to do that anyway considering the low cost of serial encoders. (Aircraft Spruce has a TSO’d serial encoder for $240.)
