Electrical Cranks but No start with the key...will start jumping the solenoid

[Grrranimal69]

83 CJ7 AMC 258 i6 / 4.2l ....cranks with the key, will not start....will start with the key on and jumping the solenoid...switched solenoid from my other jeep and still no start with the key...installed ignition switch from my other jeep and still no start with the key...installed ignition module and still the same no start unless solenoid is jumped....voltage to s and I terminals while cranking right around 10 volts and my understanding is that both should have 12 volts at start...what would cause the drop in voltage at s and i...? When the no start with the key condition started my radio blew a fuse and when I installed a new one it blew it out immediately put another and it blew it immediately...can someone help?