730: Circuit Diagram

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Circuit Diagram

Title text: I just caught myself idly trying to work out what that resistor mass would actually be, and realized I had self-nerd-sniped.

Explanation

Another fine example of nerd sniping. There are pieces of circuit diagrams, road maps, chemical diagrams, and other things all mixed in. Explanations for each below!

Transcript

Image Fragment	Image Location	Description
	106×37 @ 19,25	A map scale. Lists kilometers and miles as equivalent. And makes the diagram many miles wide.
	40×85 @ 15,62	An antenna. Typical of radio receivers or transmitters.
	41×87 @ 53,60	A coil or inductor. Normal, but unlabeled.
	85×93 @ 107,86	A cloverleaf interchange or junction is a feature of road networks that does not belong in a circuit diagram. Of course other types of junction are important in electronics
	87×63 @ 184,12	A battery. The voltage of square root of two is strange, but getting about 1.41412... volts is not unheard of. The marked polarity is also the reverse of what is implied by the symbol (where the larger terminal is positive).
	94×71 @ 187,110	A 120 ohm resistor is normal enough. "Or to taste" is odd for a circuit diagram and more like instructions from a recipe e.g. "1 tbsp tomato purée, or to taste".
	90×63 @ 283,50	A normal switch, with a notation to glue it open. Reminiscent of the MAGIC/MORE MAGIC switch.
	69×64 @ 337,101	A bipolar PNP transistor, except that it has two emitters and no collector.
	79×107 @ 52,141	Compass points. A map feature, not a circuit feature.
	63×58 @ 415,18	A normal resistor, labeled with color code. Brown-Blue-Orange would be 16000 ohms.
	42×32 @ 517,14	A normal diode.
	73×74 @ 615,55	A chip. The normal timer is a "555". "666" would be the number of the beast. The pin connected to "?" is the CTRL pin on a normal 555 timer, which would typically be connected to ground (via a decoupling capacitor) if used at all; the implication here seems to be that it would be connected directly to Hell itself.
	69×41 @ 632,138	A batman logo.
	75×71 @ 650,211	A squirrel. What it does as a circuit element is unsure.
	54×53 @ 606,165	A coil or inductor, labeled as an 11 kilogram mass.
	99×59 @ 538,209	A 240 volt AC generator (or other power source).
	111×103 @ 483,186	A shorting wire around a generator. The label reads "Omit this if you're a wimp." If this wire is included, it will quickly melt -- or worse.
	57×75 @ 419,78	A jar of scarab beetles.
	28×44 @ 482,47	A variable resistor with center tap. Normally, there would be an arrowhead on the center tap.
	22×27 @ 507,53	A normal capacitor.
	96×62 @ 577,318	"Magic Smoke" is the legendary stuff inside a chip that comes out when it fails.
	51×66 @ 669,315	Some frayed or dangling wires.
	58×48 @ 567,392	This appears to be a float used in fishing. Alternatively it might be a mine. In this case the frowny face might be a reference to the Windows game minesweeper where a smily face turned into a frowny one if you hit a mine.
	111×86 @ 458,336	A bridge rectifier, which would normally turn alternating current at the top and bottom into direct current on the left and right. In this case, it is labeled as a "moral rectifier". This is presumably a play on the idea of moral rectitude - it makes your circuit more moral. Why this matters in a circuit is unclear.
	80×85 @ 423,259	A warm front is a feature on a synoptic weather map.
	54×52 @ 190,199	A normal 50 volt battery.
	89×56 @ 173,200	A battery is grounded on both sides. Something will melt or burn out quickly, unless these are separate "earth ground"s, in which case the ground might get a bit cooked.
	174×25 @ 259,198	Text reads "Pull this wire really tight". This kind of physical property issue may indicate a high frequency radio device.
	41×91 @ 141,211	A specified 3/8 inch separation. This probably indicates a carefully controlled capacitance issue.
	92×59 @ 173,309	An electric eel. This may be an effective power source in the circuit.
	35×41 @ 266,307	A normal resistor.
	34×29 @ 222,358	A normal capacitor.
	44×40 @ 130,335	A normal resistor, labeled "ë", This may be a play on Euler's Number, which doesn't normally have an umlaut. Alternatively instead of being an umlaut it may indicate the second derivative derivative of e with respect to time in Newton's notation - in which case as e is a constant, the resistance of this element is zero.
	61×92 @ 65,249	This appears to be a blender.
	115×73 @ 20,342	An arduino, labeled "Arduino, just for blog cred."
	118×82 @ 39,423	A chip labeled "Most expensive chip available". The small curve at the top is a part of the packaging designed to show its orientation.
	91×50 @ 159,428	Labeled "Neck Strap". Perhaps a piece of torture equipment or indicating that the circuit is part of an electric chair?
	110×88 @ 147,480	A switch labeled "Hire someone to open and close switch real fast."
	61×64 @ 273,498	A 5 ohm resistor labeled "(decoy)". One end is not attached to anything.
	103×56 @ 307,453	A pair of contacts, labeled "Touch Tongue Here".
	45×45 @ 301,270	A frowny-face. See the float/mine.
	128×124 @ 294,311	A small integrated circuit. The lower gate is an inverter, wired as a free-running oscillator. The upper gate is an XOR wired to act as either a free-running oscillator or a latch. Since the XOR will be slower than the inverter, the overall output of the upper gate is probably very chaotic. Two "input" wires are not connected at all. An additional wire is hot glue'ed to the top. This last wire probably acts to control static and leakage.
	91×25 @ 302,235	A caution sign at a curve. Another road feature in the circuit.
	67×68 @ 401,455	A methyl group (chemistry) attached to a corner. If the circuit were an organic chemical, it would be reasonable to find a number of these.
	43×93 @ 453,167	A balloon, possibly blowing in a breeze.
	22×43 @ 572,68	A coil or inductor.
	42×20 @ 508,96	A coil or inductor.
	22×31 @ 534,61	A ground connection.
	134×140 @ 472,49	A solder blob covering a portion of the circuit. Normally, this would not be part of the circuit diagram, but a mistake in building the circuit.
	207×158 @ 493,443	A rats nest of 1 ohm resistors. It is labeled "Oh, so you think you're such a whiz at EE201?" Calculating the effective resistance of this is what the title text refers to. It appears to works out to 0.75800964845... ohms.
	232×200 @ 315,533	An arena, with a few bodies in it. Note the direction of movement enforced by the surrounding diodes, "two men enter, one man leaves"
	47×51 @ 569,653	A "pi" ohm resistor.
	75×70 @ 610,655	A 500 volt AC generator. The wiring to the right shorts out this generator.
	85×64 @ 481,682	A ground connection, labeled "Bury deep, but not too deep". This type of ground connection is called an "earth ground" The "too deep" part might be a reference to Moria in Lord of Rings. The dwarves dug too deeply and disturbed a balrog. See also comic 760.
	75×73 @ 17,610	A ground connection at the end of a curve, looking like a fishhook. Means perhaps "earthed down under", i.e. Australia or the southern hemisphere.
	66×45 @ 206,662	A length of "wire" is labeled "yarn". This probably makes it a terrible conductor.
	93×88 @ 102,590	The flux capacitor from Back to the Future
	54×24 @ 138,685	A road sign for "I-95". Interstate 95 is the main north-south highway on the east coast of the United States, running from Maine to Florida.
	134×36 @ 12,713	A connection labeled "To center of Sun". A 93 million mile circuit is rather large, but ...
	144×177 @ 31,753	A rats nest of wires. Everything winds up being connected.
	97×61 @ 22,513	A label reading "Electrons Single File". If this happens, the resistance in this section of wire would be rather high.
	29×39 @ 256,619	A ground connection
	58×46 @ 589,600	A vibrator, which would be a motor with an off-center weight attached to it.
	74×52 @ 532,779	A motor, labeled "To Scale". This indicates that the physical size and shape of the motor must match the size of the parts around it, or is consistent with the specified scale of the drawing.
	73×109 @ 662,822	A ground connection, in a beaker labeled "Holy Water".
	48×55 @ 197,740	A speed limit 55 MPH sign. This is a rather typical road sign, but inappropriate for a circuit diagram.
	100×116 @ 238,706	A pair of NOR gates wired as a SR (set-reset) flip-flop. The label reads "May use an actual sandal instead", which is a play on the meanings of the term "flip-flop".
	70×54 @ 322,708	Something that could be the side view of a fence, labeled "Holding Pen". There might be a small figure inside...
	42×49 @ 339,777	A simple overhand knot.
	149×33 @ 191,889	This appears to be an Electrocardiograph trace.
	82×68 @ 223,826	A photodiode, labeled "Tear Collector". A photodiode is a light sensing device.
	49×68 @ 373,859	A lamp. This is not the symbol used in electrical circuits, but a drawing of a lightbulb.
	65×32 @ 450,887	A coil or inductor.
	120×72 @ 537,847	A coil or inductor, labeled "Take off shirt while wiring this part. Ooh, yeah, I like that."
	34×41 @ 504,860	A resistor labeled "?". Presumably this means the resistance is unknown.
	55×38 @ 459,828	A resistor labeled "YES".
	58×53 @ 389,774	A resistor labeled "8mm".
	93×84 @ 443,747	A resistor labeled "Not a resistor; wire just does this". This may reflect the fact that any wire has a certain amount of resistance just by being a wire, or it may be that the wire is physically bent into a zig-zag shape.
	82×24 @ 415,863	A symbol similar to two electrolytic capacitors back to back, labeled "3 Liters". Also similar to the symbol for an orifice or flow restriction used on plumbing or hydraulic diagrams. In which case the "3 Liters" might mean 3 liters per minute or per second.