As previously stated;
Until someone actually looks at the unit on display the best guess is smoke and mirrors triggered by the loss of the drone. Even a competent Russian or Chinese technician would be able to tell.
Had Iran made such a coup; they would be more than willing to show off some of the internals and more of the unit to the world to demonstrate their superiority over the "great satan".
Look at the Pakistan handled the helo that was lost.
Perhaps Iranian people are not Pakistani in culture ? I am not Iranian myself but i do have some Iranian friends and know a little Iranian background. It is quite fascinating, the history and cultural of other countries in general. My friends not favoring the oppressing regime as it is by the way. I mean to say, look at the difference between the USA and Canada. Not that much i would say as a foreigner. Until i start calling an American a Canadian and vice versa.
When looking from a political perspective :
Perhaps they want to use it as a means of negotiation with the USA ?
Perhaps if Iran would really have a sort of intact drone, they would score points for be willing to return it to USA and not disclose any of the technology to others. This means they have political leverage. Of course they would not show this openly because several countries in the ME would not be to happy about it when Iran and the USA start to develop a good friendship( Even if that is still possible). Similar as Saudi Arabia.
(That would not mean they would not try to take a peek at it themselves. But to be honest, i doubt they have the capabilities (equipment) to reverse engineer integrated circuits. I do am sure that Iranian electronic engineers are very skilled in electronics and math.)
As a side note:
What does anybody here think about the new F-22 and the failure of the OBOGS oxygen generation system and the subsequent crash because the pilot got a disorientated ?