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2507: USV-C

2022-05-04T20:19:22Z

Muraenabeta: Undo revision 242220 by Ex Kay Cee Dee (talk)

{{comic
| number = 2507
| date = August 25, 2021
| title = USV-C
| image = usv_c.png
| titletext = Ultra-Serial Violet C light is unpolarized, so you don't have to flip the polarizing filter over when you get the orientation wrong the first time.
}}

==Explanation==
This is the fourth installment in the series of [[:Category:Cursed Connectors|Cursed Connectors]] and presents Cursed Connectors #280: USB-C to UV-C. It follows [[2503: Memo Spike Connector]] (#102) and was first followed just a bit more than half a year later by [[2589: Outlet Denier ]] (#78).

This comic depicts a cable that converts from USB-C (at the top of the picture) to UV-C (at the bottom).

{{w|USB-C}} is a rotationally symmetrical {{w|Universal Serial Bus}} (USB) connector. {{w|Ultraviolet#UVC|UV-C}} is a range of {{w|ultraviolet light}} with wavelengths between 100 and 280 nm. This is often used as a germicide, so this comic may also be related to the [[:Category:COVID-19|COVID-19]] pandemic. The U.S. Food and Drug Administration (FDA) has an [https://www.fda.gov/medical-devices/coronavirus-covid-19-and-medical-devices/uv-lights-and-lamps-ultraviolet-c-radiation-disinfection-and-coronavirus infosheet] with information about these devices and COVID-19. And the connector number (280) is likely chosen because it is the boundary between UV-C and UV-B in nanometres.

Similar cables actually exist, with a USB port at one end to power a small (usually visible light) lamp at the other. A cable with a UV-C lamp could, as noted above, be useful for disinfecting surfaces; however, the depicted design would be problematic because it would expose the user's skin and eyes to harmful ultraviolet radiation.

Unless there is more to the UV-C end than indicated, the cable seems not to have use in bidirectional communication (even to confirm that it is {{w|TOSLINK|plugged in}} or {{w|Infrared_Data_Association|shone upon}} some suitable optical transceiver) so in any {{w|Li-Fi|data transfer situation}} it could be a limited-range broadcast-only system at best - which has its uses in certain niche cases.

The title text mentions that the UV-C is {{w|Polarization_(waves)|unpolarized}}. This is a pun with two uses of the term polarized. When referring to a connector 'polarization', or absence of it, it means that USB-C does not force you to use a single {{w|Electrical_connector#Keying|correct orientation}} when using it, i.e. you don't have to turn it "right-side-up" like USB-A or USB-micro.

It also refers to the use of a {{w|Polarizing filter (photography)|polarizing filter}} which takes unpolarized light waves and blocks out the waves that are not oriented in the same direction. These are used in sunglasses and photography to eliminate glare and enhance the image. These filters do need to be oriented in a specific direction in order to have the desired effect of passing/blocking a given polarization, perhaps to separate two perpendicularly orientated 'channels' that need to be unmixed exactly knowing the respective orientation of the two signals (''or'' exactly 180° out, which is what USB-C effectively allows for at present).

The light could also have been {{w|Circular_polarization|circularly polarized}}, which allows 'left' and 'right' rotating polarizations to simultaneously carry separate signals, but {{w|3D_film#Polarization_systems|not require the same strict orientation}} to operate properly, at all, so long as arbitrary mirrors are not involved at any stage of the optical path. Regardless, the implication here is that there is ''no'' deliberate rationalization of the light to contend with, anyway, which seems to be just making a positive point out of a potentially lost opportunity to double any intended signal bandwidth. The name "Ultra-Serial Violet..." could be read as consciously eschewing ''all'' attempts at parallelism, including talkback.

==Transcript==
:[A cable with a curled wire displays the end of both of its connectors. The top end has a USB-C connector and the bottom end has a UV-C LED. The UV light is shown coming out of this end with a hazy blue circle around a white middle. The lamp is also bluish. Above is a title and below is a label.]
:Cursed Connectors #280
:USB-C to UV-C

{{comic discussion}}

[[Category: Comics with color]]
[[Category: Cursed Connectors]]

2589: Outlet Denier

2022-05-04T20:18:06Z

Muraenabeta: Undo revision 241774 by Ex Kay Cee Dee (talk)

{{comic
| number = 2589
| date = March 4, 2022
| title = Outlet Denier
| image = outlet_denier.png
| titletext = There are regularly placed bumps on the underside just the right size to press the rocker switch on the power strip.
}}

==Explanation==
{{incomplete|Created by a BIG CHUNGUS - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This is the fifth installment in the series of [[:Category:Cursed Connectors|Cursed Connectors]] and presents Cursed Connectors #78: The Outlet Denier.

The outlet denier connector in this comic is the large connector to the right. It has a plug on the downward side that is supposed to go into a {{w|power strip}} or other type of outlet. It has two long bars extending up and down off the plug, as well as a D shape on one side with another, slightly less long bar on the other side of the D, that has the cord connected to it. The purpose of the outlet denier is to block access to as many other ports on a power strip as possible, hence the name. It is designed to work with many different types of power strips, such as the standard one displayed in the comic, as well as ones with the sockets rotated 90 degrees (the long bar extending to the cord) and other types of outlets like the triple outlet on the end of many extension cords and two dimensional power strips that extend a couple of outlets left and right as well as up and down (the D shape on the side). The extreme bars to each side may also prevent plugging the Denier into an outlet close to the floor, forcing the user to use a power strip or similar item for it.

There is an example power strip displayed to the left of the outlet denier, used to help explain that the outlet denier is designed to block as many other sockets on a power strip as possible. The power strip is presumably of the type with a {{w|Light_switch#Rocker|rocker switch}} that can turn the entire power bar off. This power bar has five outlets.

Many appliances require transformers or other large components on their power cord. Sometimes these "power bricks" are built around the plug. The comic is making fun of these types of power bricks, as they often block access to other sockets on a power strip or wall outlet. This can be really annoying when you want to plug in many different appliances into a power strip.

Other plugs are deliberately designed to block the other half of a duplex outlet, preventing users from plugging anything else in that could overload the circuit. The comic could be depicting an extreme case of a cumbersome connector shape designed to block an entire power strip, as the appliance connected to it uses so much power that a single extra item plugged into the power strip would cause problems.

The title text says that the outlet denier has bumps on the underside of the long bar that would match up with the location of the rocker switch no matter which outlet of the strip it is plugged into. It's not clear whether this will turn the power switch off or force it always on. But either way, it gets in the way of the user being able to control the power themselves.

If it forces it off, then the Outlet Denier cannot even be used. So to at least assume someone might actually use it, it must force it on. Since there are nothing else that can go into the power strip, it is not that important it it is possible to switch it off though.

==Transcript==
{{incomplete transcript|Needs clarification}}
:[To the left is a power strip with a rocker switch at the top and five outlets, and a connected wire goes from the top off to the left. To the right is the plug that should go into one of the outlets. A curved wire comes from the right and connects to the end of the connector, which is longer than a normal plug. The prongs are visible underneath where the box ends. But instead of ending there, there is a bar horizontal to the first part, which is longer than the power strip itself. There is a D shaped bar attached to this long bar, centred on the middle of the bar. If it was plugged in, the long bar would cover all the other outlets of the power strip.]

:[Text above the image:] Cursed Connectors #78
:[Text below the image:] The outlet denier

{{comic discussion}}

[[Category: Cursed Connectors]]

2495: Universal Seat Belt

2022-05-04T20:15:45Z

Muraenabeta: Undo revision 241772 by Ex Kay Cee Dee (talk): Reverted vandalism

{{comic
| number = 2495
| date = July 28, 2021
| title = Universal Seat Belt
| image = universal_seat_belt.png
| titletext = The plug fits really snugly, so it should be safe in a crash.
}}

==Explanation==
This became the second installment in the series of [[:Category:Cursed Connectors|Cursed Connectors]] and presents Cursed Connectors #65: The Universal Seat Belt. The series began two comics earlier with [[2493: Dual USB-C]] (#187) and was followed three weeks later by [[2503: Memo Spike Connector]] (#102).

The comic shows another of [[Randall|Randall's]] "Cursed Connectors", the "Universal {{w|Seat belt|Seat Belt}}" — a pun on the Universal Serial Bus ({{w|USB}}) connector — which would have the same abbreviation of USB.

USB connectors are mostly designed for free and unrestricted insertion and removal. There may be a slight use of the internal and external bumps and dimples to provide a tactile indication of being engaged or disengaged, but there are usually no facilities to prevent a connector being easily pulled out of even a port being actively used - the OS can do no more than complain that a device has been removed without first ensuring proper logical unmapping of the resource (which in turn may have to await a current session of data transfer being completed or aborted) or warn that a "delayed write" has failed. Anyone who has used USB in a frequently-jostled environment knows the connectors can't withstand much jerking around without their connection to their mainboard permanently failing.

Car seat-buckles, on the other hand, have very definite requirements to not come loose ''unless'' intentionally and mechanically released, in order to keep the passenger safely anchored to the seat.

The title text claims that the seat belt is secure in the case of a crash. This is another pun, as seat belts protect passengers in a car crash while USB standard is designed to protect the computer in the event of a device hardware malfunction.

Another similarity between seat-belts (especially on back seats) and USB-plugs is that they can be a bit fiddly to insert. A seat-belt lock with the asymmetric design of a USB-A plug would be even more fiddly and thus "cursed".

One possible use for the USB data connector might be to give a certain degree of 'proof' that the belt is plugged in, although that functionality is fairly well covered by current anchor-point sensors that (combined with seat-occupancy sensors that may respond to the weight of a seated person) can trigger dashboard lights and possibly warning sounds in vehicles as necessary to prompt correct usage of restraining belts. That system does not usually need an electronic data connection between anchor and belt, an anchor-side switch should suffice, and it would still require a mechanical gripping/hooking method to make it of any use to be engaged in the first place.

The USB specification is designed such that USB connectors fit snugly from pressure. This means they usually need no button, like seatbelts have, to lock them in place. If one hacks a USB connection to increase the tightness, so that it can withstand more force applied to it and still hold its function, it becomes much harder, or even impossible, to insert and remove. Randall has removed the button, such that the connectors are a "cursed" misleading and dangerous use of similar form.

==Transcript==
:[The two ends of a seatbelt are shown next to each other, but the seatbelt connectors are replaced with a USB-A plug and port. Above is a title and below is a label.]
:Cursed Connectors #65
:the Universal Seat Belt

{{comic discussion}}

[[Category:Cursed Connectors]]