2503: Memo Spike Connector

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Memo Spike Connector
Backward-compatible with many existing cables, and can connect directly to phones or tablets if you press them down hard enough.
Title text: Backward-compatible with many existing cables, and can connect directly to phones or tablets if you press them down hard enough.


This is the third installment in the series of Cursed Connectors and presents Cursed Connectors #102: The Memo Spike. It follows 2495: Universal Seat Belt (#65) and was followed 9 days later by 2507: USV-C (#280).

The comic depicts a large metal spike with a wire coming from the base. The spike stabs through two other wires, thus creating an electrical connection between the three. As the name suggests, the spike resembles a stationery spindle, colloquially known as a spike, called a Memo Spike here by Randall. However, unlike normal spindles, this one has a cable of some kind coming out of it, suggesting this is a hub of some sort.

Spindles are used to temporarily hold paper by "spindling" or impaling the paper onto the spike (as depicted in the comic). They're most known for their use in restaurants as a way to hold bills that have been paid, or traditionally in offices that work with many bits of paper, e.g. with invoices in a finance department or hardcopy in newspaper editing, to prevent accidental disturbance/shuffling, at the expense of a small puncture mark in each sheet so impaled. (This could cause errors in papers with punch-holes that are meant to be read by machines, hence the admonition against "folding, spindling, and mutilating".) In the latter context, the editor might put all the rejected stories onto a spike (rather than into a wastebasket) to prevent them going astray, and this might be the source of the term 'spiked'.

The joke of the comic is while any number of non-destructive connection standards exist, a large spike can provide much of the same results: a conductive object that retains a connection of multiple wires in a way that allows electricity to pass through. Indeed, in the early days of Ethernet, vampire taps were used, essentially spikes that bit into a cable to establish a new branch in the network. Another type of connection which involves piercing the wire is a punch-down block, a type of insulation-displacement connector, where one or more wires are pushed into a cutting channel instead of onto a spike.

Depending on the type of cable it is also likely to create a short circuit, e.g. by connecting both strands of a twisted pair of strands in a typical Ethernet cable, or the central wire and the sheath of a coaxial cable. In an enterprise environment, this could even happen on a PoE-Connection, which actually carry more noticeable amounts of power (up to 25.5W). Even if this is avoided, the single spike may be large enough to mechanically sever a random subset of the finer strands that exist within a multicore cable such as is commonly in use today.

The title text takes this a bit further. It says that it is backwards compatible with many existing cables. This means any cable large enough to be impaled by the spike could be used. Needless to say it will likely not work anyway. It also continues by saying that phones and tablets can also be connected using this method if you press them down hard enough over the spike. Thus if you actually manage to make the spike penetrate the device's coverings to reach the electrical parts, then there is a connection. The implication is that any device or cable can be connected to any other device or cable as a form of universal adapter/splitter/combiner across arbitrary hardware and communications/power standards. In reality, this could be even more dangerous and will surely destroy the phone/tablet either directly or by overloading their cable connection. Also be careful not to impale your hand while trying to push the spike through your tablet's screen.


[A memo spike is shown (a device also called a Spindle). It is a long spike standing up from a round base plate. A wire is coming in from the left and appears to be hardwired into the spike's base element. Two other wires comes in from the right. Both are firmly impaled down upon the spike, penetrated completely through shortly before their apparently unterminated ends. The end of the impaled wire closest to the base faces out and the details appear to show it to be of some variety of multicore (rather than co-axial) manufacture. The other cable's end is a bit higher and points into the image. Above is a title and below is a label.]
Cursed Connectors #102
The Memo Spike

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Just made my first ever wiki edit! There was no text yet so I filled in some basic info. I guarantee what I wrote will be removed though :( . Oh well, I tried! Zman350x (talk) 15:20, 16 August 2021 (UTC)

Your first edit inspired me to my own first edit. Maybe at the end there will be a good article made entirely by noobs. :) 16:33, 16 August 2021 (UTC)
Seems like some parts of your edits have survived, to what seems close to a final version now. Any start on an explanation is difficult so cool that you are now on the editing team ;-) I make a lot of edits, but is not typically the one that makes the actual explanation, more keeping the format and making small improvements --Kynde (talk) 07:20, 17 August 2021 (UTC)
 :o -- 10:55, 17 August 2021 (UTC)

In restaurants these are not used for orders for the kitchen. Those are usually put on an order wheel or ticket holder, which have clips that the order can easily pulled out of. The spike is at the checkout counter, and it's used after the bill is paid. Barmar (talk) 19:57, 16 August 2021 (UTC)

Do we want to mention the vampire taps in both the article and trivia? Cause that's how it currently is. Zman350x (talk) 21:27, 16 August 2021 (UTC)

No. Have removed trivia. --Kynde (talk) 07:20, 17 August 2021 (UTC)

My first comment too! Where it says... "The implication is that any cable can be connected to any other cable as a form of universal adapter/splitter/combiner"... That's not the title text joke. It's that a device like an iPad could also be impaled on the spike, making electrical connection to its innards. It says nothing about cable to cable connections. 21:47, 16 August 2021 (UTC)

Didn't see this comment until I intervened, under the same impression, but I totally agree. Looked like an orphan comment intended for the pre-titletext 'explanation'. Still valid, and rather than move it I expanded it to fit better where it is. Doubt it'll be the 'final' version, though. (Anecdotal explanation of my thinking: If I put my tablet down on my opened laptop, it'll sometimes 'agitate' the laptop trackpad. Technically I could probably get the tablet to control this inbuilt mouse deliberately through whatever ¿field-effect? is interacting with the ¿capacitative? finger-sensor. I am imagining something like this (only more puncturing!) is what is 'promised' if I impale two otherwise incompatible devices on the same spike. But also lets one connect otherwise incompatible cables to further cables/devices. Like I don't have an ethernet dongle that works with the tablet, but spike them both and I'd be laughing.... Right?) 03:14, 17 August 2021 (UTC)
The title text is also about old types of cables and not just smartphones and tablet. --Kynde (talk) 07:20, 17 August 2021 (UTC)

This explanation does not answer the one question I came here to find the answer to, namely why it is named “memo spike.” 03:19, 17 August 2021 (UTC)

Some (not me, but that's because I've never used one in anger, maybe) seem to call the non-connector thing that the connector is based around a "memo spike". Apparently one can impale successive memos (in a memo-heavy administration job?) upon the spike and then later thread a chord (or treasury tag?) through the holes to perpetuate their 'spiked collection' status. It's possible there are other names (like: thumb-tack <=> drawing pin), but this is how Randall identifies it. Better than "that thing you spike paper onto - but now with power!!!111oneoneone", etc... 'Though YMMV. 03:56, 17 August 2021 (UTC)

The detail on the free cable end is more clearly visible in the double-sized image version, suggesting that it isn't just a coax. BunsenH (talk) 04:28, 17 August 2021 (UTC)

It is actually the x2 version that is now showed per default on the xkcd page, and thus it is that one that should be used here on xkcd.. ie. the one you are presented with on xkcd. Have uploaded that version to explain now. --Kynde (talk) 07:20, 17 August 2021 (UTC)
"It is actually the x2 version that is now showed per default on the xkcd page" - you're wrong about that. The x2 is an optional image if the markup-linked code decides it wants to make it the embedded image. Maybe that becomes default in your case, but don't assume it's true for everyone, all the time. (You can break the explainxkcd page rendering for people, like me, if you force a typical x2 image into here, even when xkcs original is sane and allows deliberate zooming.)
My suggestion in this case/similar is to clip the detail from the x2 to highlight the feature and embed this exact bit in the explanation, if you want to make sure everyone sees the high-res version of that bit in particular. 13:41, 17 August 2021 (UTC)
I have added an imagesize parameter, so it renders with the 'standard' size while keeping the detail from the 2x version when viewing the file's page. theusaf (talk) 16:32, 17 August 2021 (UTC)
Sorry about this. I have reverted to the normal size image. And removed the size change, which causes confusion, see below. I thought that when the link to the image is called 2x on xkcd it was that image being shown there. I wil also change the other one that I have put in 2x image, and refrain from doing so again! --Kynde (talk) 10:28, 19 August 2021 (UTC)

Possibly a reference to the 1987 movie RoboCop; the titular character had a similar looking data spike used to interface with OCP computers. 19:16, 17 August 2021 (UTC)

Similar looking? It's a spike, which is action-relevent at another point in the movie (or maybe franchise, if I'm thinking of some sequel/requel scene). But not (if I'm not missing anything by my dotty memory) a thing with a round base that acts to vampire-tap cables. 02:23, 18 August 2021 (UTC)
This here looks pretty much like the comic to me and it is a data connector. 18:54, 18 August 2021 (UTC)
I would concur in that "It's a spike". Yes used (there) for data, but it's just a sharp pointy thing, in the way that all rockets are phallic, and only looks like a bit of the connector. You could equally try some other thing to part-compare with on the same basis. 21:18, 18 August 2021 (UTC)

It would be interesting to get a list of cable types for which this could actually work in some circumstances. Also how would the device deal with multiple cables being impaled on it as in the picture? How would the information be separated? 07:42, 18 August 2021 (UTC)

Even with one cable, it would need to be a majority-insulating spike with a myriad of pin-prick conductive patches arrayed (like a ring-barelled audio+ connector, but radially distinct also) each ready to leach one and ony one bit of bare copper (though a wire may/should touch multiple spike-patches) without bridging to another.
All these would need bundling into the base - or maybe with very clever in-spike isolation/relaying conductor paths - for any currents to be assessed and sorted and build up a logical picture of whhat the few contact-patches that are contacting wire are actually contacting (perhaps moment to moment, as movements of the impaled cable happen).
For 'passive' wires in the bundle, maybe tentative pulses can detect the altered capacitance/impedance they give the patch-spots, then (from clues based upon any active signals) a complex and careful handshaking attempt would need to auto-negotiate which kind of auto-negotiating might be expected by the device(s) at the other end(s) of the cable.
Hopefully enough connections exist to operate any particular carrier-cable correctly (single-pair +/-, or ground/pos/sig+/sig-, or DA+/DA-/DB+/DC-/DC+/DB-/DD+/DD-, or whatever), and with enough current capacity without cross-conductor signal-lraking (either physically or inductively). Adding a second cable (which may jostle the first, requiring hot/on-the-fly reinterpretation of its patch-mapping and capabilities therefrom) just repeats the process with previously untouched patch-contacts.
...and if you can get that working. You're welcome to the patent. A similarly dynamic 'induction/inducer clamp' version might be my own prefered choice, but probably also difficult to get working well (for different reasons). 12:30, 18 August 2021 (UTC)

Why is there a [click comic to enlarge]?Or am I having problems?1337-PI (talk) 00:32, 19 August 2021 (UTC)

Yes that was partly my fault by putting in the 2x image instead of the regular. Then someone put in a size in wiki which causes that line. I have reverted and removed the imagesize. It should work now. See above. --Kynde (talk) 10:28, 19 August 2021 (UTC)

This is mostly a jab at puncture industrial automation buses? Like https://www.bihl-wiedemann.de/en/company/technological-foundations/bus-systems/asi-bus-system.html