730: Circuit Diagram

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(Explanation: Discovered that I had listed two wired-together nodes as not connected. (I was thinking of seeing if I could get it as a rational...))
(Explanation: used "Star-mesh transform"s to get more precision.... haven't got rational yet...)
Line 69: Line 69:
{{circuit-diagram-part|X=534|Y=61|W=22|H=31|image=circuit_diagram-534-061-022-031-ground.png|text=A ground connection.}}
{{circuit-diagram-part|X=534|Y=61|W=22|H=31|image=circuit_diagram-534-061-022-031-ground.png|text=A ground connection.}}
{{circuit-diagram-part|X=472|Y=49|W=134|H=140|image=circuit_diagram-472-049-134-140-solderr-blob.png|text=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.}}
{{circuit-diagram-part|X=472|Y=49|W=134|H=140|image=circuit_diagram-472-049-134-140-solderr-blob.png|text=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.}}
{{circuit-diagram-part|X=493|Y=443|W=207|H=158|image=circuit_diagram-493-443-207-158-res-rats-nest.png|text=A rats-nets of 1 ohm resistors. It is labeled "Oh, so you think you're such a whiz at EE201?" [http://www.wikihow.com/Calculate-Series-and-Parallel-Resistance Calculating the effective resistance of this] is what the title text refers to. It appears to works out to 0.75801 ohms.}}
{{circuit-diagram-part|X=493|Y=443|W=207|H=158|image=circuit_diagram-493-443-207-158-res-rats-nest.png|text=A rats-nets of 1 ohm resistors. It is labeled "Oh, so you think you're such a whiz at EE201?" [http://www.wikihow.com/Calculate-Series-and-Parallel-Resistance Calculating the effective resistance of this] is what the title text refers to. It appears to works out to 0.75800964845... ohms.}}
{{circuit-diagram-part|X=315|Y=533|W=232|H=200|image=circuit_diagram-315-533-232-200-arena.png|text=An arena, with a few bodies in it. Note the direction of movement enforced by the surrounding diodes, {{w|Mad_Max_Beyond_Thunderdome|"two men enter, one man leaves"}} }}
{{circuit-diagram-part|X=315|Y=533|W=232|H=200|image=circuit_diagram-315-533-232-200-arena.png|text=An arena, with a few bodies in it. Note the direction of movement enforced by the surrounding diodes, {{w|Mad_Max_Beyond_Thunderdome|"two men enter, one man leaves"}} }}
{{circuit-diagram-part|X=569|Y=653|W=47|H=51|image=circuit_diagram-569-653-047-051-resistor.png|text=A "pi" ohm resistor.}}
{{circuit-diagram-part|X=569|Y=653|W=47|H=51|image=circuit_diagram-569-653-047-051-resistor.png|text=A "pi" ohm resistor.}}

Revision as of 07:33, 9 January 2013

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


Ambox notice.png This explanation may be incomplete or incorrect:
Please include the reason why this explanation is incomplete, like this: {{incomplete|
If you can address this issue, please edit the page! Thanks.

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!

Image Fragment Image Location Description
circuit diagram-019-025-106-037-scale.png 106×37 @ 19,25 A map scale.
circuit diagram-015-062-040-085-antenna.png 40×85 @ 15,62 An antenna. Typical of radio receivers or transmitters.
circuit diagram-053-060-041-087-inductor.png 41×87 @ 53,60 A coil or inductor. Normal, but unlabeled.
circuit diagram-107-086-085-093-cloverleaf.png 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
circuit diagram-184-012-087-063-battery.png 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.
circuit diagram-187-110-094-071-resister.png 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".
circuit diagram-283-050-090-063-switch.png 90×63 @ 283,50 A normal switch, with a notation to glue it open. Reminiscent of the MAGIC/MORE MAGIC switch.
circuit diagram-337-101-069-064-transisitor.png 69×64 @ 337,101 A bipolar PNP transistor, except that it has two emitters and no collector.
circuit diagram-052-141-079-107-compass-points.png 79×107 @ 52,141 Compass points. A map feature, not a circuit feature.
circuit diagram-415-018-063-058-resister.png 63×58 @ 415,18 A normal resistor, labeled with color code. Brown-Blue-Orange would be 16000 ohms.
circuit diagram-517-014-042-032-diode.png 42×32 @ 517,14 A normal diode.
circuit diagram-615-055-073-074-666timer.png 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.
circuit diagram-632-138-069-041-bat.png 69×41 @ 632,138 A batman logo.
circuit diagram-650-211-075-071-squirrel.png 75×71 @ 650,211 A squirrel. What it does as a circuit element is unsure.
circuit diagram-606-165-054-053-inductor.png 54×53 @ 606,165 A coil or inductor, labeled as an 11 kilogram mass.
circuit diagram-538-209-099-059-generator.png 99×59 @ 538,209 A 240 volt AC generator (or other power source).
circuit diagram-483-186-111-103-shorted-generator.png 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.
circuit diagram-419-078-057-075-scarab-beetles.png 57×75 @ 419,78 A jar of scarab beetles.
circuit diagram-482-047-028-044-variable-resister.png 28×44 @ 482,47 A variable resistor with center tap. Normally, there would be an arrowhead on the center tap.
circuit diagram-507-053-022-027-capacitor.png 22×27 @ 507,53 A normal capacitor.
circuit diagram-577-318-096-062-magic.png 96×62 @ 577,318 "Magic Smoke" is the legendary stuff inside a chip that comes out when it fails.
circuit diagram-669-315-051-066-frayed-wires.png 51×66 @ 669,315 Some frayed or dangling wires.
circuit diagram-567-392-058-048-buoy.png 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.
circuit diagram-458-336-111-086-moral-rectifier.png 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.
circuit diagram-423-259-080-085-warm-front.png 80×85 @ 423,259 A warm front is a feature on a synoptic weather map.
circuit diagram-190-199-054-052-battery.png 54×52 @ 190,199 A normal 50 volt battery.
circuit diagram-173-200-089-056-shorted-battery.png 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.
circuit diagram-259-198-174-025-pull-wire.png 174×25 @ 259,198 Text reads "Pull this wire really tight". This kind of physical property issue may indicate a high frequency radio device.
circuit diagram-141-211-041-091-3-8-inch.png 41×91 @ 141,211 A specified 3/8 inch separation. This probably indicates a carefully controlled capacitance issue.
circuit diagram-173-309-092-059-eel.png 92×59 @ 173,309 An electric eel. This may be an effective power source in the circuit.
circuit diagram-266-307-035-041-resistor.png 35×41 @ 266,307 A normal resistor.
circuit diagram-222-358-034-029-capacitor.png 34×29 @ 222,358 A normal capacitor.
circuit diagram-130-335-044-040-resistor.png 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.
circuit diagram-065-249-061-092-blender.png 61×92 @ 65,249 This appears to be a blender.
circuit diagram-020-342-115-073-arduino.png 115×73 @ 20,342 An arduino, labeled "Arduino, just for blog cred."
circuit diagram-039-423-118-082-meca.png 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.
circuit diagram-159-428-091-050-neck-strap.png 91×50 @ 159,428 Labeled "Neck Strap". Perhaps a piece of torture equipment or indicating that the circuit is part of an electric chair?
circuit diagram-147-480-110-088-switch.png 110×88 @ 147,480 A switch labeled "Hire someone to open and close switch real fast."
circuit diagram-273-498-061-064-resistor.png 61×64 @ 273,498 A 5 ohm resistor labeled "(decoy)". One end is not attached to anything.
circuit diagram-307-453-103-056-tongue.png 103×56 @ 307,453 A pair of contacts, labeled "Touch Tongue Here".
circuit diagram-301-270-045-045-frown.png 45×45 @ 301,270 A frowny-face. See the float/mine.
circuit diagram-294-311-128-124-IC.png 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.
circuit diagram-302-235-091-025-curve.png 91×25 @ 302,235 A caution sign at a curve. Another road feature in the circuit.
circuit diagram-401-455-067-068-CH3.png 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.
circuit diagram-453-167-043-093-baloon.png 43×93 @ 453,167 A balloon, possibly blowing in a breeze.
circuit diagram-572-068-022-043-inductor.png 22×43 @ 572,68 A coil or inductor.
circuit diagram-508-096-042-020-inductor.png 42×20 @ 508,96 A coil or inductor.
circuit diagram-534-061-022-031-ground.png 22×31 @ 534,61 A ground connection.
circuit diagram-472-049-134-140-solderr-blob.png 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.
circuit diagram-493-443-207-158-res-rats-nest.png 207×158 @ 493,443 A rats-nets 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.
File:circuit diagram-315-533-232-200-arena.png 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"
circuit diagram-569-653-047-051-resistor.png 47×51 @ 569,653 A "pi" ohm resistor.
circuit diagram-610-655-075-070-generator.png 75×70 @ 610,655 A 500 volt AC generator. The wiring to the right shorts out this generator.
circuit diagram-481-682-085-064-ground.png 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.
circuit diagram-017-610-075-073-fishhook.png 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.
circuit diagram-206-662-066-045-yarn.png 66×45 @ 206,662 A length of "wire" is labeled "yarn". This probably makes it a terrible conductor.
circuit diagram-102-590-093-088-fluxcapacitor.png 93×88 @ 102,590 The flux capacitor from Back to the Future
circuit diagram-138-685-054-024-I95.png 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.
circuit diagram-012-713-134-036-tothesun.png 134×36 @ 12,713 A connection labeled "To center of Sun". A 93 million mile circuit is rather large, but ...
circuit diagram-031-753-144-177-rats-nest.png 144×177 @ 31,753 A rats nets of wires. Everything winds up being connected.
circuit diagram-022-513-097-061-esf.png 97×61 @ 22,513 A label reading "Electrons Single File". If this happens, the resistance in this section of wire would be rather high.
circuit diagram-256-619-029-039-ground.png 29×39 @ 256,619 A ground connection
circuit diagram-589-600-058-046-vibrator.png 58×46 @ 589,600 A vibrator, which would be a motor with an off-center weight attached to it.
circuit diagram-532-779-074-052-motor.png 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.
circuit diagram-662-822-073-109-holy-ground.png 73×109 @ 662,822 A ground connection, in a beaker labeled "Holy Water".
circuit diagram-197-740-048-055-speed.png 48×55 @ 197,740 A speed limit 55 MPH sign.
circuit diagram-238-706-100-116-flipflop.png 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".
circuit diagram-322-708-070-054-holdingpen.png 70×54 @ 322,708 Something that could be the side view of a fence, labeled "Holding Pen". There might be a small figure inside...
circuit diagram-339-777-042-049-knot.png 42×49 @ 339,777 A simple overhand knot.
circuit diagram-191-889-149-033-ecg.png 149×33 @ 191,889 This appears to be an Electrocardiograph trace.
circuit diagram-223-826-082-068-photodiode.png 82×68 @ 223,826 A photodiode, labeled "Tear Collector". A photodiode is a light sensing device.
circuit diagram-373-859-049-068-lamp.png 49×68 @ 373,859 A lamp. This is not the symbol used in electrical circuits, but a drawing of a lightbulb.
circuit diagram-450-887-065-032-inductor.png 65×32 @ 450,887 A coil or inductor.
circuit diagram-537-847-120-072-inductor.png 120×72 @ 537,847 A coil or inductor, labeled "Take off shirt while wiring this part. Ooh, yeah, I like that."
circuit diagram-504-860-034-041-resistor.png 34×41 @ 504,860 A resistor labeled "?". Presumably this means the resistance is unknown.
circuit diagram-459-828-055-038-resistor.png 55×38 @ 459,828 A resistor labeled "YES".
circuit diagram-389-774-058-053-resistor.png 58×53 @ 389,774 A resistor labeled "8mm".
circuit diagram-443-747-093-084-resistor.png 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.
circuit diagram-415-863-082-024-unsure.png 82×24 @ 415,863 A symbol similar to two electrolytic capacitors back to back, labeled "3 Liters".



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So, is the arena a new kind of comparator or something? Davidy22[talk] 13:28, 18 February 2013 (UTC)

11:13, 10 April 2013 (UTC)11:13, 10 April 2013 (UTC)Jh6p (talk) The 3 liter capacitor could also be a ball approximately 6 inches in diameter if the seams on the ball were similar to the seams on a basketball. Perhaps a volleyball?

"A squirrel. What it does as a circuit element is unsure."

Perhaps an allusion to a squirrel cage? Wwoods (talk) 18:51, 22 April 2013 (UTC)

The shape of the squirrel's tail reminds me of a hysteresis curve, although this is admittedly a bit of a stretch. —Scs (talk) 16:02, 17 November 2013 (UTC)

The 'to scale' motor would be about half a mile wide. Powering the rabbit on Gaia's vibrator (also included)? --StarChaser Tyger (talk) 08:40, 22 June 2013 (UTC)

I beg to differ on the flux capacitor thing, as cool as it sounds. Since it is right above the I-90 notation, it is more likely a fork in the road (notice the road stripes indicating that you can pass at any point in the fork). 02:15, 24 June 2013 (UTC)

Oh, I'm pretty sure it's a flux capacitor. Compare some of these images. Yes, there are several road references in this comic, but an electronic reference (especially to a fictional electronic component!) makes more sense. Also I've never seen a Y-shaped highway intersection that looked quite like that (and especially not on an interstate). —Scs (talk) 14:52, 17 November 2013 (UTC)

I have wasted 4 hours on the puzzle, and after wasting 9 pages of A5 paper, the resistance of that terrible resistor mess worked out to be exactly 25265/33783 ohm, or about 0.74786135 ohm. --KopaLeo 15:16, 27 June 2013 (UTC)

I think that the "fishing float" might actually be a picture of an ordinary push switch (similar to foot switches used on standard lamps). 16:12, 10 July 2013 (UTC)

Isn't the "YES" resistor a reference to the anecdote of how John Lennon and Yoko Ono met? That's what I thought when I saw it, but then, I kinda like The Beatles a bit. 12:27, 16 September 2013 (UTC)

I think the attempt to explain every single piece of the comic is rather silly. The humor largely draws from the absurdity of the diagram, and that can probably be summarized without going into detail about the possible references of each individual component. 03:22, 26 November 2013 (UTC)

I disagree. The joke works on multiple levels, both the absurdity of the circuit, and the smaller parts of which it is comprised. Hydroksyde (talk) 02:40, 21 April 2014 (UTC)

I concur with KopaLeo - I got the same answer for the resistance of the grid of resistors - about 0.748 when rounded. What a problem! --techdude 20:45, 1 January 2014 (UTC)

I feel like I should point out that putting a ground connection in holy water probably creates Holy Ground 11:36, 26 March 2014 (UTC)

To center of Sun could possibly be another map reference. 01:08, 19 November 2014 (UTC)

The 'moral rectifier' seems like it's built of diodes which prevent current flow to the left, which might mean it's making the current 'more right'? with right being a synonym for moral? 00:15, 17 December 2014 (UTC)

3L capacitor

The capacitor reminded me of a time I asked my dad why desktop PCs (the kind we could afford at the time were 200-500 W) couldn't have capacitors to protect them from 1-second or shorter power interruptions without the cost of a UPS. He said such a capacitor would have to be as wide and tall as a 2L pop bottle. (He didn't say how much it would weigh.) Promethean (talk) 04:38, 9 September 2014 (UTC)

Where did the claim that the EKG is atrial fibrillation come from? At best it it hard to tell without a time scale what the ventricular rate is, but there is no evidence of extra P waves between QRS complexes that I see. If the diagnosis is made based on the absence of P & T waves, keep in mind that some recording conditions make those (especially T) hard to see. In an Einthoven's triangle arrangement, they might not show up at all above the noise. If we had a time scale that let us calculate ventricular rate, we might be able to conclude supraventricular tachycardia, but I'm hesitant to make a strong claim that this is abnormal at all given that it's hand drawn and we have no scale.Djbrasier (talk) 21:07, 22 January 2015 (UTC)

Does this really belong in Category:Charts? I'm moving it to Category:Maps instead. gijobarts (talk) 21:38, 19 February 2015 (UTC)

Are we really explaining "vibrator" as "a motor with an off-center weight attached to it"? 06:51, 13 March 2015 (UTC)

I just spent 3 hours trying to work out the resistor nest. I was unsuccessful. Mikemk (talk) 05:32, 19 March 2015 (UTC)

I did an LTSpice simulation or the resistor mess. It looks like the 25265/33783 ohm answer above is correct. It drew 1.3371463 amps from a one volt source. (talk) (please sign your comments with ~~~~)

Based on Randall's promotion of international standards (such as ISO 8601), it seems odd that he's using the US zigzag symbol for a resistor, rather than the IEC rectangular one. Walale12 (talk) 21:37, 17 April 2015 (UTC)

Looking at the label "Tear Collector" I think it refers to the heartbeat below it, not the symbol above, suggesting that a heart (or heart break) is a likely source of tears. (talk) (please sign your comments with ~~~~)

I'm not sure why the rat's nest of resistors is considered such a difficult problem. I would like to respectfully point out that by far the easiest way to solve it is by assuming a constant current through the network. You can then assign a name to each of the nodes, set one of the end nodes to 0V, and solve by KCL. Granted, there are 13 unknowns and 14 equations, but it still took less than 30 minutes to complete since they are all 1st order! archerator Archerator (talk) 04:57, 30 August 2015 (UTC)

120×72 @ 537,847: the coil symbol next to "Take off shirt while wiring this part. Ooh, yeah, I like that." is similar in appearance to chest hair in stylized comic strips. Thaledison (talk) 17:19, 5 October 2015 (UTC)

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