Then Alternators themselves on page 91, the main AC generators on an aircraft — Page 282, Lesson 287

This is the index of the book, so it's a map of the topics we'll cover. Let me walk you through the key entries you'll find under the letter A and the start of B, so you know what's ahead. We begin with Actuators on page 110 — these are the devices that physically move control surfaces or other mechanisms in response to electrical signals. Then Alkaline Battery on page 58, a type of rechargeable cell you'll see in some aircraft systems. Next is the ALL or NOTHING Gate on page 264 — that's a logic gate in digital electronics; it outputs a signal only when all inputs are present, or none at all. Alternate Action on page 29 refers to a switch that changes state each time you press it, like a push-on/push-off button. Alternator Cooling on page 201 is exactly what it sounds like — how we keep the alternator from overheating during operation. Then Alternators themselves on page 91, the main AC generators on an aircraft. Aluminium on page 254 is a material we'll study in the context of semiconductor doping — it's used as a p-type dopant. Ammeter on page 5 measures current in amperes. Ampere Hours (Ah) on page 54 is a unit of battery capacity — it tells you how many amps a battery can supply for one hour. Amperes and Amps on page 5 are the same thing: the unit of electric current. AND Gate on page 264 is another logic gate — it outputs a signal only when all its inputs are high. Antimony on page 253 is an n-type dopant, added to silicon to create extra free electrons. ANY or ALL Gate on page 265 is a logic gate that outputs when any or all inputs are present, depending on configuration. Apparent Power (VA or kVA) on page 175 is the product of voltage and current in an AC circuit, measured in volt-amperes or kilovolt-amperes — it's different from real power because of phase shifts. Armature on page 85 is the rotating part of a generator or motor where voltage is induced. Arsenic on page 253 is another n-type dopant. Autotransformers on page 232 are transformers with a single winding that acts as both primary and secondary — they're lighter than conventional transformers. Auxiliary Power Unit on page 204 is the APU, a small gas turbine that provides electrical and pneumatic power on the ground or in flight. Under B, we have Back EMF listed twice — on pages 85 and 107 — that's the voltage generated in a motor's armature that opposes the applied voltage, limiting current. Base on page 258 is one of the three terminals of a bipolar transistor. Batteries on page 53 is the general chapter on battery types and characteristics. Bimetallic Switch on page 30 uses two metals with different expansion rates to open or close a circuit when heated — a thermal switch. Binary Logic on page 263 is the foundation of digital systems, using ones and zeros. Bipolar on page 257 refers to bipolar junction transistors, which use both electron and hole charge carriers. Bonding on page 145 is the electrical connection between metal parts of the airframe to ensure a low-resistance path for static discharge and fault currents. Brushed Alternators on page 193 use brushes and slip rings to transfer current to the rotating field. And Brushless Alternators — the entry cuts off, but you can expect them on the following pages, using a rotating rectifier assembly instead of brushes. That's the index for A and the start of B. These are the topics we'll work through in detail as we go.