Take the D scale for example. Start on the D note at the second fret and move up the scale like this to the next D: If you play this same pattern up two frets (so the E is the first note you play), youâll have an E major scale. The same goes for any other pattern you can spot in these scale maps.
A pacemaker signals the heart to beat when the heartbeat is too slow or irregular. A pulse generator is a small metal case that contains electronic circuitry with a small computer and a battery that regulate the impulses sent to the heart.
A permanent pacemaker or ICD has three main components: 1  A pulse generator which has a sealed lithium battery and an electronic circuitry package. The pulse generator produces the electrical signals that make the heart beat. 2  One or more wires (also called leads).