 All right, the great search with Digikey and Lady Eda. They're the ones who do this. Thank you, Digikey. Okay. Lady Eda uses all her engineering skills to search the Digikey site. So what is this week's great search, Lady Eda? Okay. I'm designing a board with the new ESP32S2, which is a Wi-Fi chip. And hold on, here we go, schematic checklist. And to this chip, it has native Wi-Fi capabilities. All you have to do is plug in a inductor and two capacitors, and then an antenna to make for very easy Wi-Fi connectivity. People love the ESP32 series. And usually I use a module, but for this design, I have to go wheel small. It has to fit in the size of a coin. It's very tiny, this little board. I think it's like, you know, one inch, like point eight inches by point seven inches. So very small. So don't have space for a module. Instead, I'm gonna put the raw chip on with any passive components and end antenna. So I have to go and find a inexpensive surface mount antenna that's small enough to fit on this PCB. So I thought let's go to Digikey and start that search. So it's Wi-Fi. So we want a Wi-Fi antenna. And basically antennas can be tuned to different frequencies. The frequencies that we want are 2.4-ish gigahertz. Luckily, there's a lot of people making Wi-Fi connected electronics. And so we're not gonna have to search it that hard to find it. If you're doing something with like 110 megahertz or something that's not a standard ISM band, you're gonna have to search a little bit harder or it might actually be easier because there's less options. But for us, let's just search for Wi-Fi antenna. Okay, so all sorts of antennas, modules, accessories, all this stuff. Well, we just want the antennas themselves. Obviously that search will pop up any Wi-Fi module that also has antennas. All right, let's go for active parts. Oh, look, there's us. And let's look for normally stocking and RoHOS compliant, because that's what our minimums are. We want something that comes in a tape and reel, so not a tray or bulk. And that will cut down just so we're looking at components that aren't on a tray because there's some larger antennas that come bulk. We don't want like a duck antenna. We want like a little surface-bound antenna. Okay, next up, there's a lot going on here. There's like so many frequency ranges and I kind of was like, oh my God, what am I doing here? But the first thing you wanna check is like, well, how many bands are you gonna do like Wi-Fi and cellular? Are you doing, like, not different protocols but different bands, like Bluetooth and Wi-Fi and ZigBee and Thread, they're all gonna be 2.4 gigahertz. So you don't have to worry about that, but if you're doing, you know, there's some here that are like, oh, they do GPS or cellular plus Wi-Fi, then you'd want a multi-band antenna. In our case, one band is enough. Okay, cool, so we're actually pretty much, you know, we've really dropped down to only 79 options or so, which is good. So, you know, here's where you can go for like the gain, right, you know, the highest gain possible, but the problem is that we're constrained by space and the larger the antenna in general, the better the gain you're gonna get. You just have, you know, more space to work with when it's small, you have to do like funky tricks to get it to resonate at the frequency that you want to transmit at. Okay, so let's also go for the centerband frequency. So we want the centerband about 2.4 gigahertz. Do you remember there's also five gigahertz Wi-Fi? We're not doing that. Okay, so far so good. Okay, so let's look at some of the options we have here. So here's some cool things. So there's like pillar antennas. These are antennas that stick up or they pick in place and you put them down and they stick up out of the PCB. I can't unfortunately use these. There's also a lot of like these little, like you can see there's like a multi-layer, like there's some sort of like multi-layer fractal antenna thing going on here, just pretty cool. I'm probably gonna pick up a couple different antennas to try out. We know if I look at ones like these, I can kind of tell they're probably not gonna fit. These are longer ones. But anything that looks long, I don't think I'm gonna be able to fit because I need kind of something short and squat. But there's antennas like this. And one thing I did, you know, my favorite thing is I searched by reverse stock number to see the most popular ones. These are the, you know, I've seen these antenna, these bent metal antennas on U-Blocks modules. They're apparently quite good. And what's neat is, you know, they pick in place and they seat into like little holes on the PCB and they go above the PCB. So you get nice 3D radiation. I saw a couple designs with these fractus antennas. So, you know, the question is like, well, which antenna? Also these like, these are super cool, like cyberpunk, like 3D Molex antennas. I've seen these, I think, I think like the small, I don't remember like the teeny tronics, somebody who makes a very small electronics and they use these antennas. But the antenna that I'm actually gonna use is, oh, it's interesting. It's not, why didn't it come up? Hold on, it is the, cause I actually used this part. This is the AT-40, I wonder if I, where do I need to go? So this is the antenna that I used on the circuit playground blue fruit. So let me show that off. So if you see this little antenna here, this is the same antenna. It's a little tall, but what I like is it's very compact. It's like about the same size as a 1206 resistor. So this is the antenna that I'm probably gonna pick up just because I already have these. And again, they're like, they're really inexpensive. They're only about 25 cents a piece. However, I also want to try out like these practice antennas and this bolex antenna because this looks cool. Like this is very compact and it sticks up. And especially if the price isn't too bad, so let me put down 1,000. And you can see like, for 25 cents, there's a lot of like 20, oh here it is. So for like 25 or 30 cents, there's a lot of little nubby antennas that I can try out. So the good news is that you don't have the exact right package on your layout. So I'm probably just gonna use like the Johansson, you know, kind of sort of standard little nub antenna footprint and then I'm trying to probably solder in different ones. And then I can use a spectrum analyzer. I have a little Latini one. Or what I've also done is just a distance test. Like I just have, I just see how far away I can get from the router before it stops working or I can measure the RSSI and just say like, okay, of these four boards I made, which one has the lowest RSSI? And that tells me which one the antenna is working out for. So there's a lot of options, try them all. One thing that was, you do have to watch out for, it's not a big deal, but there's only the height, the size isn't mentioned. So you're going to have to use the photos and dig into the datasheet to find the dimensions of the antenna and then, you know, any layout recommendations. There's also like these gigantic patch antennas. I mean, if you want something with just like really great gain, like these are awesome, but they're gonna be expensive. Okay, so the one I ended up saying I'm gonna go for is this one, 2450-18V100. There's another couple that are very similar, but they're thinner. This one is a little bit bigger, but I've used it really successfully with all sorts of Bluetooth projects. So I think it'll probably work out for this Wi-Fi project as well. But if people have suggestions for a Wi-Fi antenna that is really small, let me know because I've never had to make such a small Wi-Fi board before, but we'll come back on another Jessica Ladiata and see how this antenna fared. That's great search. Where is it?