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Super capacitor for daytime-only solar nodes?

Hear me out. I've been thinking about the best way to put up solar nodes in my area.

I live in Michigan so the winters are long and usually cold, and can get quite cold on occasion. Less so these days, but still. We all know that lithium doesn't like to be charged below 32f, so that's a problem.

I have one idea for a remote node on my property, to just use a 6v sealed lead acid with a 6v solar trickle charger, maybe a diode in series to the node if the voltage from the panel threatens to go over 7 or 8 volts. Or some kind of shunt, idk that idea isn't fully baked.

I'm also looking into a thermostatically controlled resistive heater. Bump up the capacity of the battery and make sure the panel is big enough to run the heater non-stop if need be. But that idea is also still baking, parts are in the mail and prototyping is yet to be done.

But then I had another idea. What about super capacitors? You can get a 5.5v 10F super capacitor on Amazon for $6. Some chatgpt math (and a proper understanding of the difference between power and energy, or rather ma vs mah) tells me that the storage 10F at 5 ish volts is equal to a nominal lipo at 3.7v and 10mah. Ignoring the fact that the capacitors voltage would drop sooner, and thus you'd lose some energy on the bottom end...

The T114 v2 has a built in solar charger circuit, a standby current of 9ma, and a TX draw of 150ma. So with a super capacitor you could get roughly an hour of idle time, or 4 solid ish minutes of nonstop transmitting. That's more than enough to account for a big cloud passing by, especially if you beefed up the solar panel, or easier yet just doubled or tripled the capacitors, they are pretty small.

The charging circuit might not like the low internal resistance of an empty capacitor every sunrise, but a couple ohm resistor in series would probably solve that.

Yes it's not ideal to have your nodes turning off every night, especially in the winter when days are short to begin with. But could it technically work? I feel like it could technically work. It'd be great in the summer,

My only concern would be the node getting stuck in a weird state if the sky is cloudy and the CPU browns out. It'd take a whole day to power cycle. Probably put a megohm resistor across the capacitor to ensure that it drains fully overnight in that scenario.

Are there any concerns with constantly hard power cycling a node like that? Data corruption?

The lead acid is probably the safest solution, though heavy. And the heater is probably the most compact solution, though more complicated and prone to catastrophic failure. But maybe there is room for super capacitors?

Sorry for the wall of text. Just spit balling.

Edit: HOLD THE PHONE! You can get 500F caps for $7! The reviews say they're actually more like 300F, but even that could idle a node for well over 24 hours, and TX nonstop for 2 hours, which is unlikely to happen. This is a game changer. This could solve the winter lithium problem.. I'm going to try this and I'll report back.

0
Winter Driving
  • Nope, made it scarier.

    Also bad is when the big flakes are coming down heavy, flying over your windshield, lit up by your headlights. It's like your flying at light speed, hard to see the road

  • How accurate is the meshmap?
  • Yeah a bummer. But I've still got plans to get some height, and I've got some friends who are gonna join in on the fun, I'm hoping we can mesh our houses 😁

    Yep everything is default. US, longfast 🤷‍♂️

  • How accurate is the meshmap?
  • So far no nodes other than the two I bought. I got the upgraded longer antenna, and went out on my second story balcony in a suburban area, nothing.

    Looks like I'll be the change I want to see in the world haha.

  • How accurate is the meshmap?
  • So far no nodes other than the two I bought. I got the upgraded longer antenna, and went out on my second story balcony in a suburban area, nothing.

    Looks like I'll be the change I want to see in the world haha.

  • How accurate is the meshmap?
  • So far no nodes other than the two I bought. I got the upgraded longer antenna, and went out on my second story balcony in a suburban area, nothing.

    Looks like I'll be the change I want to see in the world haha.

  • How accurate is the meshmap?
  • Honestly the Amazon antenna will probably do perfectly fine, I might go that way for simplicity sake.. maybe I'll build an antenna too and do some a/b comparisons.

    The 90 degree angle doesn't hurt performance inherently, it only hurts it because it puts the antenna right next to the body of the radio, blocking some of the signal, and detuning the antenna slightly as well. So you're still better off putting it vertical 👍

    Also in case you didn't know, those antennas are vertically polarized. That means when the tip is pointing up to the sky, the signal is coming out the sides going off towards the horizon. That's the best way to get a signal out/in. Holding it sideways will create null points from the tip and base of the antenna, and also send half your signal into space and the other half in the ground 😁

  • How accurate is the meshmap?
  • Looks sweet. I might end with something like that eventually, but honestly I really like the idea of using my phone and just linking the mesh device to it. Reminds me of the old goTenna before they sold out.

    Do you have somewhere high you could mount a repeater/router node to? Like the chimney of your house or something? Would make it even easier to connect with people, at least from home.

    I'm planning on putting a few up, one at my house and each of my buddies houses.

  • How accurate is the meshmap?
  • Thanks! You mean I should get some of those sma adapters and some of those little stick antennas? Or something even bigger? Recommendations?

    I'm a ham and I've got a nanovna, I could try making a ground plane antenna for 915mhz.

    My plan is to put a repeater/router up on my tower 30ft up, as well as on a couple of my friends roofs, hopefully making a stable emergency channel between us. I'm between my buddies, 13 miles between the furthest ends, I'm almost in the middle.

  • How accurate is the meshmap?

    I'm still fighting with Amazon to get my first pair of devices delivered, I went with heltec v3s to get started.

    But looking at the meshmap.net, it's very very sparse around me. How likely is it that the are nodes that aren't on the map?

    Hopefully I can check it out myself soon!

    23
    What's something unique that you carry on you every day?
  • Small high power flashlight, about the size of a tube of m&ms. People laugh at it all the time, but it comes in handy weekly, sometimes daily.

    Think of how many times you pull out your credit cell phone light. Now imagine being able to light up a room like daylight if need be. Very useful.

    Those same people who laugh, eventually realize the value, and come asking for my light when we're together and it's needed

  • Gyro input broken on HZD? My last playthrough it was working fine, now it seems impossible to make it work. Am I an idiot or did some configuration get broken in the last year?

    I'm trying to configure the gyro to help me aim. I've tried every configuration I can think of, or find online. I'm slamming head into a wall.

    From what I can tell, the game now only accepts "steam controller" input. Which means the right joystick isn't actually a joystick, it's a weird virtual joystick, and there's some conversion going on. So when the old methods for getting gyro input are used, ie "as joystick" or "as mouse", the input is completely ignored by the game.

    I've tried configuring a fresh controller configuration based on a standard controller, but then the game things I'm trying to use a keyboard and mouse and ignores all controller input.

    Now, if I set gyro to "right stick (steam controller logo)", then suddenly the gyro starts affecting the right stick. But instead of being a relative input, as in when I pull the left trigger to aim, use the current gyro position as zero, and all relative movement should be applied to the stick. Instead it is an absolute value, with the movement being relative to the calibrated location of gravity down. So when I pull the left trigger, I immediately stare into the sky.

    I think the solution to this is the "auto world tilt" option, but that is only available in the "gyro to joystick" configuration, which of course doesn't work.

    Am I missing something completely obvious here? Can someone please guide me in the right direction? I miss gyro aim.

    Thanks

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    Framework 16 power supply, 65 watt?

    Hi there, I've been wanting a framework for awhile now, just haven't pulled the trigger yet. I was perusing the website today, comparing the price and performance of different configurations, when I realized that the 16 needs a 100w power adapter, 180w if you've got the graphics card.

    This is a dumb question, because obviously it would charge fine with the lid closed and idling or turned off. Or I could just upgrade my power adapters. But I have a lot of 65w USB C PD chargers in my house and cars, and I was wondering if anyone has tried using them, and if so how effective is it?

    Like, 180w is a lot of power. If I'm just working on spreadsheets or something, I'm imagining it would charge just fine? Under a heavier load I would probably start to slip backwards? Where's the line? Movie watching? Light gaming?

    Just food for discussion I guess, I still haven't pulled the trigger haha.

    Thanks!

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    Anyone tried Kopi Luwak coffee?

    The civet processed beans? I'm wondering if it's all hype? Or worth buying a bag to try?

    Edit: Thanks for the responses everyone! I'm gonna pass on it 👍

    8
    Any recommendations a two person backpacking tent? Preferably one during this REI sale?

    I'm new to backpacking, did my first trip this year with a hammock and had a great time.

    Trying to get my wife into it with me. We're planning on going to Iceland in September, no trees. Plus she sleeps cold so she'll probably be more comfortable if we're in the same tent.

    I'm looking to spend as little as possible, we're really not sure this will be our thing going forward, it might just be something I do solo. And we already have a big six person tent for glamping with a big air mattress.

    I'm hoping for under $200, less if possible.

    But I also don't wanna buy garbage, or carry something excessively heavy.

    Suggestions?

    Edit: this seems popular and well liked? https://www.rei.com/product/185632/rei-co-op-half-dome-sl-2-tent-with-footprint

    14
    InitialsDiceBearhttps://github.com/dicebear/dicebearhttps://creativecommons.org/publicdomain/zero/1.0/„Initials” (https://github.com/dicebear/dicebear) by „DiceBear”, licensed under „CC0 1.0” (https://creativecommons.org/publicdomain/zero/1.0/)BE
    beastlykings @sh.itjust.works
    Posts 7
    Comments 155