Calling A and P and IA repost after bizarre glitch.

[65eTurbo]

So, I'm looking at some used avionics.  Anyone here with expertise and without a business model to protect that can set me straight.  I'm patching together info from multiple sources.  I'm looking to establish what is legal, not what is safe.

Used avionics dealer sells equipment without 8130s, claims that installing said equipment is legal if an IA makes a log entry - "Removed xx, Serial Number yy, replaced with xx equipment, serial number zz."  Is that true without an 8130?  

Second question, say I wanted to replace a T & B with a TC using the same log entries, would that still be legal?

Third question, if I install a new transponder consistent with an STC and that STC made freely available by the holder, do I need anything more than an IA signoff "Installed aaa transponder in accordance with STC 12345.... blah blah blah" and a pitot static check?

Fourth question, if I install a GPS source bought used without an 8130 that is part of that STC and verify operation via the transponder computer check and a ground check, is that legal or is an 8130 or C o C required?  

Fifth question, am I asking the right questions?

Thanks.

Rant about STC installs limited to dealerships, pricing supports, absurdity of separate avionics components when it could all be one much cheaper box, big players forcing out little players by gumming up obtuse and unnecessary certification processes, the perpetual life of government bureaucracies etc. withheld.

[carusoam]

See answers here...

Best regards,

-a-

[Baker Avionics]

Customer supplied ANYTHING, in essence, can be installed without a 8130.  This isn't magic or anything.  Most of it is common sense to a point where, I, personally, and am sure @carusoam feels the same way as we chat a lot on here, would NEVER install anything on my plane without some sort of guarantee that it , at least, should work, with paperwork to back it up. If "a guy" wants to put something "as removed" on his airplane, go ahead and do it with a log entry, which, for the most part, is completely legal and move out smartly if there is no requirements needed for RTS.