Dual transponders

>>Wrong>>>>It doesn't matter all transponders use only 29.92" of Hg to>>transmit altitude so an errant altitude setting doesn't>throw>>off the radar.>>It will most certainly show an altitude error on radar. Atc>radar is adjusted for local altimeter. If you use the wrong>setting then you will be off altitude and your pressure>altitude being transmitted will show the deviation.I should have replied with the quote I was responding to. "Usually the second transponder is tied to the right seat altimeter, so that while the guy in the right seat is flying that second transponder is reporting his altitude, which may not be the same as what the altimeter is reporting in the left seat."Not exactly true in how it was worded. It does not matter what altimeter it is tied to if it is tied to one at all.