Power...Over An Ethernet Cable?
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- Опубликовано: 28 мар 2022
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Did you know you can power some devices using just an Ethernet cable?
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Наука
I'm actually more impressed by the analog clock that has to physically move to sync itself to internet time.
Servo motors!
We have one that uses radio waves to keep time. Its never wrong and sets summer/winter time automatically :D
We have those clocks all over our hospital
@@AK90 I have it but it doesn't set time at the right day but a random day
@@AK90 At my work they have a clock like that, but that one never works😂😂
Oh boy. Ok, a few things here.
POE - Passive 12VDC or 24VDC. NOT negotiated... the power is passively put on the cable. This standard is obsolete and should no longer be used (though some security systems still use it and try to market it as something cool or special, it's really just old and should no longer be used). NO short circuit protection, NO voltage fail-safe, limited range, very limited power at range due to the voltage drop on the cable.
POE+ - 48VDC (typically originated at 56VDC), up to 100W for commercial POE+. But roughly 60W is typical for consumer POE+. This standard can go much, much longer distances and still provide most of the ingress power due to the higher voltage. The power is negotiated between the two ends, so POE+ and normal non-POE ethernet can be mixed together without having to worry about causing problems. The switches and clients determine the actual amount of power needed and refuse connections that exceed available power.
Your description of how POW puts power on the cable is completely wrong. Its just a DC level. The ethernet comms are differential signals that simply run on top of the DC level. Nothing swings between positive and negative voltages, certainly not the data signals! POE uses a 12V or 24VDC, POE+ uses 48VDC. The actual DC voltage injected is usually around 15% higher in order to be able to supply a decent voltage at the end of the cable. By supplying a higher voltage, POE+ loses less power over the cable over distance because the current is lower. And also because the voltage is higher, POE+ can supply far more power than the original POE standard could.
Over 100M cables are supported by POE+, as long as you take into account the greater voltage drop. Some POE+ switches have a 'range extender' switch which bumps the voltage up a bit more. However, gigabit ethernet is generally limited to 100M so if you go over that it is a good idea to use a POE+ forwarder to extend the range further.
Do not use POE injectors if you can help it, that's straight out dumb... only use an injector if you have no other choice. Almost all POE injectors use the POE standard and not the POE+ standard, and they all tend to be severely limited in how much power they can actually inject.
Just make your router a POE+ switch and you are basically done. I recommend switches that can supply at least two full-power 60W outputs.
Forwarding POE+: You can have multiple switches and forwarders. You can extend a cable with another POE+ powered switch, *OR* you can use a POE+ forwarding switch. Forwarding switches are powered from the ingress POE+ ethernet and do not require separate power. These usually have two output ports (30W input, 15W outputs) or four output ports (60W input, 15W outputs), plus of course the ingress port.
--
You can fan-out POE+ as much as you like as long as the power negotiations between devices succeed. However, you must be sure not to exceed the power capabilities of the powered switches.
POE+ security cameras typically burn around 6W each. Slightly more if motorized but that isn't usually concern. So, for example, a single 100W switch can handle around 16 cameras.
POE+ WIFI routers usually burn around 15W each. They tend to be fairly power hungry, so care must be taken to make sure you can properly power multiple WIFI routers.
-Matt
A few corrections because much of this is also wrong
PoE doesn't refer to passive PoE, it refers to the 802.3af standard and is 48V negotiated delivering up to 15W power
PoE+ is the802.3at standard and gives 48V up to 30W
Poe++ is the 802.3bt standard is up to either 60W or 100W depending on if it's type 3 or type 4
Passive PoE doesn't adhere to any standards, it's completely fine to use as long as you know not to plug the wrong shit into it, active PoE is the future sure but devices have historically remained cheaper due to reduced complexity by using passive PoE. Maybe it doesn't affect small consumers but makes a difference to the bottom line when you are installing 100's of devices.
Nice addition dude.. thank you
I remember that some landlines actually provided power to the phone that connected to them, so they'd work even during a blackout.
my old phone growing up in the 90s was like that. You could dial and receive calls, but the led display wouldnt work.
All phones in 🇬🇧 did that as a standard
All PSTN, POTS or EPOTS lines do, maybe on extremely long lines it might need a booster or something but I've seen lines of over 5km work fine. The phone-output of a DSL or cable-modem also gives out 48 volts. ISDN is worse though, that gives out 96 volts at rest.
What's a land line 🤔 🤣
I think that still works if you have a landline that can run off that power alone
I used to work for an AV and Automation installation company and we used PoE everywhere we could. It was extremely convenient to just have PoE because other than not having to worry about power outlet locations, our commercial switches usually had remote control software to allow us to remotely power cycle devices over PoE. Most commonly used in Access points and security cameras for us.
I am not sure about the technical explanation. I thing the POE transfer the power as a common DC. Meaning, the swing of the data signal stays the same but it "rides" on a DC signal.
Correct, there were a few other technical mistakes in this video as well.
It's really annoying when RUclipsrs make videos just to create content, but they don't understand the subject they are talking about. Rather than being helpful and explaining how something works, the video ends up creating confusion.
Thank you. I noticed that also.
I learned about PoE in college, when my assignment was to set up 10 cameras in college area grounds, easier to mount, and less cable management, but was pain in the a** setting ethernet cable through entire roof, patch panel or wall to make it look pretty! LOL
did you get paid? wtf
That doesn't sound like an "assignment" - that sounds like full fledged work
@@estusflask982 Sadly no, it was last year for college and before final exam we had to "work" for companies, as interns, for 6 months, but I asked if I could stay in college, as intern, because I knew that companies wouldn't teach a lot, around my place, and high possibility that for exam presentation I would have to BS a lot, to meet the minimum requirements, but as for college, they gave me stuff to do, and I did it for 7 hours a day, didn't have to worry about sitting and planning some made up story for presentation + had really good practice, if I made mistakes, it was "eh", but if I made mistakes for company "I would have to pay back the damage".... :|
@@lucaswyrm7323 How can a company asks you to pay back the damage if you're unpaid? Either it was a bluff, or you live in some terrible place.
I learned about PoE in college too! I was trying to connect my laptop an access point on an empty hostel floor so I could download faster than everybody. Then I saw that the access point only have 1 port XD
I absolutely love Techquickie. Lots of informative tech stuff I never knew existed.
They have a mostly software audience, so it's easy to find hardware/microelectronics subjects that most of the audience doesn't know about.
Pretty much every EE hobbyist, technician or engineer already worked with a microcontroller board that has a power over ethernet port, but software guys? For them ethernet is internet.
This tec has existed for years only before you had to wired in your own power feed to the lan cable. I have been doing it personally for my outside WiFi extension for around 15 years 😂
ruclips.net/video/7iSC9yXxVVc/видео.html
@@user-ju8qg9dx9x That definitely explains it. I'm a software dev, so a lot of things things are always new to me. I love it
Some still don't exist the way described here.
He is wrong in 2 major details
PoE can be confusing at times, but it’s great. I have a bunch of PoE devices in my house. PoE switches and wireless access points. The other network I manage has a remote station ran by solar that has 3 PoE cameras, and a PoE wireless bridge to connect to the base station. It’s a powerful system for powering devices. There’s smart PoE and passive PoE. Make sure the switch you are buying can provide the power you need for your device and that the PoE standards are compatible between devices and you’re good to go!
Solar powered security system sounds pretty cool.
@@SnifferSock yeah it is really neat actually. Helps us keep an eye out for predators attacking the ducks on our duck pond.
@@FoolOfATuque you're a farmer? 😎
@@nerd2544 I just help with the farm sometimes. It’s a very little one.
Serious question: what happens if you plug a non POE client into a POE port on the switch? Will this harm the client?
POE has been around a long time. Used it for years professionally
I've heard the term for a while but just never bothered to look it up lol
Exactly, ALL my security cameras, and my VOIP phones are running on POE. Even one of my Pi4s are running on POE+...
Wasn't expecting the "Never more” joke and I'm as disappointed in myself as I am amused by it.
And you flubbed the description of how it works. How it REALLY works is that each twisted pair carries data, and that data eventually goes to a transformer (a "magnetic" in networking speak). So the transformer just passes the difference in the signals. You can also put a DC voltage over the pair too, and the transformer will happily ignore that. So if you have two differential pairs, you can put a voltage across those (you also need some inductors to get the power, but block the data from getting in on the power lines).
Just wanted to say similar thing. On regular network, data transmission uses just two pairs of cables, while on PoE network, other two are used for power, usualy 12VDC. In this situation Cat6 or Cat7 are better cause their pairs are separated by foil and plastic splitter inside.
Its not a transformer, its a differential amplifier. A transformer wouldnt work well at the switching speeds of modern Ethernet. But yeah - it only passes the signal difference, it doesnt care about the offset.
Its sad LMG are getting so much simple stuff just outright wrong these days.
Yep, yet another networking related video where they are *so close* to being correct.
@@mycosys transformers do still work at 10gig. TG10G-RP02NJLF for example
@@victortitov1740 you are right. And btw, there must be a transformer between the Ethernet chip and the connector, for DC decoupling and insolation purpose.
I have a HP 2530-48G-POEP Switch that is the backbone of my network. Use POE for my Router, Cameras, Rassberry Pi-Hole. Love the flexablility and I have my main VLAN for computers and APs, then a VLAN for Cameras, and a VLAN for Iot devices.
nice, is the guest channel on a separate vlan ? the main vlan is not the hardware default i hope.
@@jyvben1520 I don’t use a guest Network, I don’t let outside devices on my network, i have a management VLAN that only allows a single client IP to access.
PoE splitter rarely works with a standard PoE switch, unless they are "passive". So, beware.
One thing I love is that Ethernet Repeaters can be powered with PoE, pretty cool
Yeah that's been a life saver for me in the past. It's rare when doing a legitimate install, but every so often it's the best option.
Just use fiber for a run that long...
Now that we learned about PoE, what about EoP? Those little devices you plug into the wall to turn your home wiring into a Ethernet system.
That's officially called Powerline, and I think there's already a Techquickie on it.
Love the video. But to nitpick, it would be more complete if there was a mention of the obscure passive Poe.
This has been amazing for some of my security cameras. Running a single cable to the cameras is a godsend.
There is something else to keep a watch out for with PoE is where manufacturers make the selection of devices difficult when they have PoE devices in there product range that use 24V. Then you have to get additional 48V to 24V dongals to put in line with them.
yeah, some security ip cams need 12volts, some outdoor wifi need 48 volts
in their product, dongles
You have to do Ethernet over Power next!
Powerline that is 🤔
Well, I get that TechQuickie needs to simplify stuff, but that simplification went all the way to “wrong“. Instead of a fine opportunity to explain differential Vs common mode voltages, something not too difficult to grasp, they handwaved it to differential voltage just being bigger. That's just wrong. At that point, you'd have been more correct saying "It just works, don't worry about it“.
I hope they will address this and make a correction :(
Heh, they are bunching together the "dumb" PoE kind that just uses a wire pair for power transmission with active PoE too, for that matter. The adapters at 4:05 are for dumb PoE or chinesium-grade PoE
Came here to say this, glad someone else caught it as well.
That is not how PoE carries power at all.
PoE really changed the installation industry, both decreasing some aspects of work as well as opening up new product lines for the client to purchase
I remember the early standard being limited to 10/100 Mbts due to the 4th pair originally being reserved for voltage,
when I went to a presentation that sold a Gigabit PoE device I had to call bullshit, only to be schooled on the new standard that Techquickie kinda explained here
“That Raven Guy.” Lol!
powerful message, ngl
That was so funny!!!! Wowwww 👍👍👍🤣🤣
SIIIIKKKEEE 😐😐😐😐😐😐😐😐🤓🤓🤓🤓🤓🤓
@@PizzaPowerXYZ Thanks, I 'shockingly' found it funny myself ;)
Oof
(also first btw)
This is the technology used by the lighting control systems I work on are powered.
A nice little reminder for me when I start back next week!
Thanks, Techquickie!😁
POE splitters(as opposed to injectors) are actually pretty cool for powering things like Ring(or any wireless security system) base stations!
I ended up running CAT6A into a central hallway of my house(as well as other rooms), and putting a splitter into the wall at the termination so I could locate my Ring base station there, and not have to rely on 2-3 range extenders(and their eyesore wall-warts) throughout my house, and the sketchy connection issues that come along with using too many of them.
Highly recommend POETexas splitters for stuff this, not affiliated with them or anything, but their splitters are actually standards compliant(802.3at), and they make some other really cool niche POE stuff that I've used for biz clients, as well as my own home use.
There's been some interesting development with POE in audio interfaces as of late as well. Just started using mixers and stage boxes all over ethernet.
That's cool. I'd seen some Dante PoE equipment that was just a single XLR or Jack for the times you just need a single input or output, but if full stage boxes are becoming PoE now, that's interesting to see. Though given, IIRC, Dante is the only standard that actually uses Ethernet and TCP/IP to carry the information, rather than a proprietary format (that can do as they wish with the wires in the cable as they're just using the Cat6 cable, not the Ethernet standard) like A&H's dSnake, the only actual PoE devices would most likely be Dante ones.
Wait...I think they're confusing Ethernet over Power from Power over Ethernet.
From my understanding, the former does use voltage differentials to send signals through the power lines. It's apparently surprisingly effective in certain situations. For the latter, the RJ45 standard includes wiring for both electricity and grounding in the form of the brown & white/brown wires.
Well, no. They got it wrong, but you're not right either, sorry. The wires are all there originally for data. 100M data just doesn't use two pairs of it.
There are 4 differential pairs of wires in the cable. 100Mbps only uses one pair per direction, so the first PoE standard was to simply use the remaining two for power - one whole pair for positive 48 V, the other for negative. 1 Gbps uses all four pairs for data, but as it's a differential signal, it can still send the differences on a single pair, and the PoE splitter just has to separate the differential signal (small voltage differences between wires in a pair) from the "common mode" voltage (the overall voltage the whole pair sits at). As this can, in the simplest case, be done with passive devices like chokes and caps, it's simple and cheap.
Later PoE standards extended that to all pairs.
I can't wait for the CAT16 Cable. It will provide Internet, power, HDMI, audio in and out, cloud storage, and a Bidet
Back in 2006-07 I went to high school to become an electrician. One of the jobs we got to do was to supply Ethernet to the student dormitories. We had a cabinet with our switch and the power supply, and from there it supplied 9 other dorms.We had to use some special equipment to run the wifi routers with power through the Ethernet cable, it was called phantom voltage if directly translated from Norwegian. So we had the router at each dorm with a splitter and a power unit. It worked well and saved us a whole lot of trouble instead of having to supply separate power to each router as well.
the mapping of positive/negative voltages to 1 and 0 bits is actually somewhat more complicated (mostly due to the need for clock recovery), and each of the four main twisted pair Ethernet versions use a completely different coding scheme, and the DC voltage is superimposed across two separate pairs, not by increasing the amplitude of pulses on one pair... but I guess it's close enough for this channel's audience.
I disagree that it's close enough. This show is meant to educate. Simplification is okay, as long as the explanation doesn't turn wrong. If it does, then it's actually hindering anyone who doesn't know and goes looking for more information.
i discovered this over a year ago. its so useful cause i live in the middle of nowhere, i use cell data to connect to the internet and often the power goes off. i have a 4g router poe compatible that requires 9v minimum, with an adapter to increment a usb power bank's 5v up to 9v. ready to plug in case of emergency (or to watch videos while i wait for the power to come back lol)
PoE is one of my favorite netwrok innovation. Also this video would make for a drinking game even Poe would appreciate. 👀
The 100 meter "problem" isnt a problem at all... Since certified data over copper is pretty much always slightly less then that.
Most interesting one in a while! Very good!!!
This is such a good video! I’m building my first house rn and I plan on using some POE devices and this explained basically everything I wanted to know!
As an AV installation tech, my advice is to make sure to sure to use at least CAT6a cables in the house for as much as you can. They will give the best performance. Making sure you have a convenient place to place the switch and everything will make troubleshooting easier if you don't have to crawl in a small closet or something to do it. Kind of an aside, but making sure you think about how an internet technician will hook up their cables to your network switch location is good, pre-running a fiber cable, CAT6, and coax cable for them to where to want your modem to be from near your electric meter will make your installation so much faster.
What a weird coincidence. Just setup my first PoE device at home earlier today, a used Ruckus R500 to replace a failing AP.
Nice and clear explanation!!
Liked & subscribed. Thanks for the clear explanation!
Features a bunch of Ubiquiti equipment and fails to mention their arbitrary use of 24V instead of the standard 48V
Ubiquiti uses active POE now not passive POE
If you work in an office setting, your EVOIP phone is likely POE. Security cameras as well.
I had a poe injector all this time accumulating dust and didn't even know what it was until now, thanks. Techquickie saving lives one video at the time.
"Nevermore"
Corvus Corax after finding an ethernet cable
In the old days we were powering a switch by using the white-brown and brown of the ethernet cable, and connecting them to the + and - wires of the adapter.
Love it!!! Thank you..
Thanks for the video.
I finally understood which port is which in the PoE injector :D
Passive PoE is not mentioned which is an unofficial standard that older devices sometimes use. Using passive PoE on a device that isn't expecting it CAN CAUSE DAMAGE. It doesn't negotiate like most PoE. Make sure your devices use the correct configuration!
Really helpful. As an individual that has deployed Ubiquiti Devices. Good to know there are different POE standards. One thing I didn't know. Thought it was all just plug and play
I use poe injectors as repeaters in my tech go bag. Used them a couple times temporarily when I didn’t have a long enough cat6 cable.
I ended up having a bunch of poe injectors that came with access points. But I didn’t need them because my switch was already poe. So this was a great way of not wasting them.
The explanation of how PoE signals are modulated is COMPLETELY WRONG in this video. The way Ethernet cables carry data is through differential pairs of wires, i.e., signals are encoded as high or low voltages between a pair of wires. There are 4 pairs of wires in Ethernet. What PoE does is connect the positive terminal of a power source to one pair, and the negative source to another pair. So the voltage difference in any pair of wires does not change whatsoever, as shown in the video. Rather, there is a voltage between one pair of wires and the other.
As someone who works in the industry, that stood out to me too, haha. He's kinda referring to PoDL (power over data line)? But yeah, PoE basically sees each pair as an individual conductor. Also depends on what type of PoE you're using. Type 1 and 2 only utilize two pairs (up to 30 W at the PSE) and Type 3 and 4 use all four pairs (up to 90 W at the PSE).
+1
@@michaeldodds6092 Not to mention the dumber versions of PoE that just omit entire diff pairs from being used for data and use them solely for voltage and ground. Those only go up to 100mbit, but they're obviously much much cheaper to implement, so they have their place.
Center-tap transformers. Anyone who works in professional AV will recognise the technique: It's the same way phantom power is delivered over an XLR connection.
This reminds me as a kid where I would be so Amazed how my mom would be able to use the house phone even though the power went out.
Feeling like I'm beefing up my internet degree with Techquickie! Thank you SO much!
My friends dad is running a start up on wiring buildings with Ethernet so all the lights are smart immediately after installation and tons less wires. He using acrylic panes for the ceiling for demonstrations
Use all of this for my job, definitely useful 👍
love these videos
Ethernet cables can also be used to send an HDMI signal (therefore offering a display output). It's positively surprising what they can do!
I work in school IT support and some of our classrooms are setup that way. There are Ethernet cables run from the teacher station to the IFP/projector and have either a VGA or HDMI over Ethernet adapter plugged into both ends. Pretty neat stuff.
This is called HDBaseT for the un-initiated.
Used where you get long runs where HDMI just can't get to, you have a transmitter at the video source, HDMI from there to transmitter, then CATx cable to an HDBaseT receiver for the projector/TV at the other end, with HDMI plugging into that device.
You forgot that the 100W PoE adapters powers some of the satellite internet dishes.
Does this remind anyone else of KipKay's video "FREE Hidden Electricity!", in which KipKay gets electricity through a phone line?
How is this man so entertaining while explaining tech stuff? It's ridiculous.
The animated twist at the end ahahaua
POE also can have different wire pairs used, so be on lookout for that as well
Only thing to amend to this: only use an injector if you have just one or two devices and have no plans to go beyond that. Beyond one or two and the switch is more cost-effective, and takes up less space. But having a spare injector does allow you to test and configuring new PoE devices before deploying them.
I wish they'd have at least mentioned passive PoE here.
With PoE (802.3af), PoE+ (802.3at), and PoE++ (802.3bt), voltage is negotiated between the switch and device - AP, camera, whatever - as long as those devices support those standards.
With Passive PoE, voltage (24 or 48 volts) is applied to the cable and sent down to the device without negotiation, whether it supports it or not.
Another cool thing about PoE++ (802.3bt) is that you can use it to power other, smaller PoE switches. Ubiquiti's USW-Pro-24-PoE can do this. One day I'll put one of those in my rack to power a USW-FLEX, which will in turn power a couple cameras and AP.
Lol at the Edgar Allen Poe references. Good old high school English classes.
Given how familiar I am with the opposite (Ethernet to powerline adapters), this is interesting
PoE= Have ethernet cables but not much electrical.
Powerline adapter= Have electrial cables but not much ethernet.
I loved the ending, Riley is amazing
Funny fact, both injectors you showed at 3:43 are actually from ubiquiti. The first is their newest model that can provide the PoE AF standard, and the first is the old passive 24v injectors they used to use with older Access Points like 7 years ago.
I use PoE on a daily basis. Glad to see it explained here. PoE injectors can be a pita. PoE switches are a must if you have multiple APs and cameras remoted from an NVR.
0:15 "PoE, not to be confused with-"
-Me: Path of Exile!
-Riley: "Edgar Allen Poe"
oh, right, that too
this is so helpful
Bruh. What a timely video. Installing 8 POE reolinks this week!
This is great. This is the way to make boring information interesting. Keep it up!
That's like ancient technology, 99% your cameras outside your office are PoE powered
4:03 I actually do this!
I use PoE for some Raspberry Pis, and I use the same hardware to basically turn ethernet cables into extension cords for things like smart lights, or older generation Google Home Minis
There's a power over POTS thing used to power phones in my office. And probably every office with an AUDIX/messaging system lol.
My school is 100% on those PoE internet clocks (the analog ones too!) And I have access to the room with the super basic master clock. I always wondered if it would make a good senior prank to go in and roll the clock back a few hours
Some Architectural lighting also uses poe and data
Me who maintains my grandparents analog survailence system: imagine not having power and video in one cable older than me
I use POE a lot at my job! Its really helpful for internet access points (boosters) and such.
There are also some POE to USB power with Ethernet. Or even small gateway PCs and Raspberry PI you can run of POE.
02:39 The Pronstache make it even better
...with the raven guy! lol!
PoE is also used in digital signage, (called PoH or Power over HD-BaseT in that context), PoE++ originated from PoH as a mechanism to power entire TV screens and push content from a single ethernet cable
Frc uses Poe to power the radio module. That way there is no barrel plug that can come unplugged.
These guys just read my mind..Ive had a PoE injector lying around all along and didn't know what it was for until now.
What was with Michael Bolton at the start? 🤣🤣🤣
I'll be honest. A network tech myself, I was able to get an Aruba AP working at 460 ft over POE with full throughput. Your mileage may vary
Some solutions let you run longer than 100m using PoE, but at slower speeds like 10Mb. Still enough for a camera, but it might be 250m away.
If I use a PoE injector both cables should have standar configuration or the PoE cable needs to be crosscable?
In the uk, out telephone lines alo caryy power, meaning that LPD's such as simple homephones can be powered by the phone jack.
PoE uses DC offset to deliver power, not larger signaling voltages...
DC offset moves the '0' point of an entire differential pair to +48v, so that where you used to have -1, 0 and +1, these become +47, +48 and +49 respectively (exadurated example)
lol I like this guys style. Totally has a clean LTT feel to the video haha
Lots of companies are starting to push POE LED lighting panels in offices too. Pretty impressive stuff.
really expensive mansions are getting that smart poe lighting too
Thx man
FYI; The background music after the sponsor ad at 2:30 is "Siamese Sea" by Epidemic Sound.
Love the crow references!
What will really blow your mind is when you learn that there are POE lights (like in office buildings). Yep, forget hiring an electrician to install a new light. Your friendly network admin can now install a light in a dark corner of the office.
One correction for this. The power transfer happens between the data-pairs. Not on the data-pair. The voltage of the differential data transmission remains the same.
in ham radio we use a bias T circuit to deliver power over the radio's coax to say a powered active loop antenna
That NEMA 5-15P device on the right in the dude's hand with the shorn off ground pin physically sucker-punched me! FOR THE LOVE OF ALL THAT IS HOLY, DO NOT USE THAT PLUG!
I was just PRAYING for a Raven joke. I didn't have to wait long...