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Solar Powered Raspberry Pi Camera

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Re: Solar Powered Raspberry Pi Camera

#21

Post by Jenda_ »

nevi-me wrote: post #9

Reading this has reminded me of something I wanted to explore in the past. Most of my applications/requirements for a Pi include GSM, but I've found GSM modules to be very expensive, often being more expensive than the Pi itself. The author mentions a mobile USB modem, and it's just dawned on me that older 3G/HSDPA dongles are often very cheap. Does anyone have experience using them, especially what power implication…

SIM800L costs $2. It supports GSM (AT commands - dialing, SMSs etc.) and GPRS (both PPP and a direct TCP connection to a hostname and port).

Regarding USB dongles, I've been running Huawei E3131 with RPi. I needed to put +5V directly onto the pin header, but maybe now with the USB-C RPi4 the power should be stable out-of-the-box. I have heard rumors that the modem freezes after a while, but I've never ran it for longer than a few days. I'd recommend either investigating whether you can hard-reset the modem with software (cycling the USB power) or even putting a watchdog that will cut power to the entire RPi.

Regarding power consumption, SIM800L is fine in idle, a few mA. However, USB dongles AFAIK do not support power save and they will eat ~100 mA all the time, which might be a significant portion of your power budget.

Re: Solar Powered Raspberry Pi Camera

#22

Post by Scoundreller »

newnewpdro wrote: post #7
nanomonkey wrote: post #2

100W solar panel seems like overkill. I'm curious what the minimal size panel one would need for 24 hour usage. Assuming 5 hours of usable sun, it would seem like a 20 W panel would be sufficient.

It's not like overkill in the solar panel department is harmful, especially if you're getting cheap chinesium stuff off ebay. Nothing helps functioning in low-light situations, like overcast and cloudy days, better than excess panel area. I have a minimally-sized panel I use for powering a laptop and it's rather annoying to have it underpowered in the slightest deviation from ideal circumstances. That same panel for…

What circuit do you use to power the laptop?

Re: Solar Powered Raspberry Pi Camera

#23

Post by Scoundreller »

mtw wrote: post #18

I see a house, why not use the Pi's Wifi instead of a modem?

Says it’s their countryside house, so may not have wifi at home.

User is somewhere in EU, and data plans can be cheaper than fixed-line connections if you use under 100gb/month.

Sometimes faster too.

Re: Solar Powered Raspberry Pi Camera

#24

Post by nevi-me »

Jenda_ wrote: post #21
nevi-me wrote: post #9

Reading this has reminded me of something I wanted to explore in the past. Most of my applications/requirements for a Pi include GSM, but I've found GSM modules to be very expensive, often being more expensive than the Pi itself. The author mentions a mobile USB modem, and it's just dawned on me that older 3G/HSDPA dongles are often very cheap. Does anyone have experience using them, especially what power implication…

SIM800L costs $2. It supports GSM (AT commands - dialing, SMSs etc.) and GPRS (both PPP and a direct TCP connection to a hostname and port). Regarding USB dongles, I've been running Huawei E3131 with RPi. I needed to put +5V directly onto the pin header, but maybe now with the USB-C RPi4 the power should be stable out-of-the-box. I have heard rumors that the modem freezes after a while, but I've never ran it for long…

Wow! Thanks, I saw SIM800L but thought that it's maybe some add-on, because the Pi/Arduino GSM components I normally see do cost more than a Pi 3. The prices that I'm seeing are an equivalent of US$10, but that's good enough.

I'll buy one and try it out. I see it only supports GPRS though, are there other cheap devices that support faster connections like EDGE/3+G? If one wants to send things like images from a camera, a faster connection would be more reliable.

Re: Solar Powered Raspberry Pi Camera

#25

Post by el_benhameen »

nevi-me wrote: post #9

Reading this has reminded me of something I wanted to explore in the past. Most of my applications/requirements for a Pi include GSM, but I've found GSM modules to be very expensive, often being more expensive than the Pi itself. The author mentions a mobile USB modem, and it's just dawned on me that older 3G/HSDPA dongles are often very cheap. Does anyone have experience using them, especially what power implication…

This isn't an answer to your question, but can you tell me more about how you source your sims/data plans?

Re: Solar Powered Raspberry Pi Camera

#26

Post by nevi-me »

el_benhameen wrote: post #25
nevi-me wrote: post #9

Reading this has reminded me of something I wanted to explore in the past. Most of my applications/requirements for a Pi include GSM, but I've found GSM modules to be very expensive, often being more expensive than the Pi itself. The author mentions a mobile USB modem, and it's just dawned on me that older 3G/HSDPA dongles are often very cheap. Does anyone have experience using them, especially what power implication…

This isn't an answer to your question, but can you tell me more about how you source your sims/data plans?

I haven't done anything practical yet, but in our country (South Africa), we've had a law recently that forces the cell network providers to allow consumers to transfer data around. For basic use (maybe 10 devices), I would be able to share my phone's data plan. I'm on a generous contract that gives me more data than I need (fiber at home).

For larger volumes, most providers will either allow you to pool a number of SIM cards' usage into a single account, especially if you restrict them to only connect to a private network. We have this at my workplace on most SIM cards in laptops.

There are also companies that supply SIMs to merchants and IoT folk on behalf of network providers. I'd also look into that. In most cases you end up with each SIM having its own data plan. I did some freelance work for one of these companies last year, if you have enough volume, you can negotiate pooling of data.

Re: Solar Powered Raspberry Pi Camera

#27

Post by nevi-me »

option_greek wrote: post #14
nevi-me wrote: post #9

Reading this has reminded me of something I wanted to explore in the past. Most of my applications/requirements for a Pi include GSM, but I've found GSM modules to be very expensive, often being more expensive than the Pi itself. The author mentions a mobile USB modem, and it's just dawned on me that older 3G/HSDPA dongles are often very cheap. Does anyone have experience using them, especially what power implication…

GSM isn't that costly: https://www.aliexpress.com/item/32827342779.html

Thanks for the link. I haven't explored AliExpress as we have a cap on how many items we can buy before we're deemed to be "importers" for customs purposes. I'll take the plunge and apply to be an "importer", so I can start buying from there.

Re: Solar Powered Raspberry Pi Camera

#28

Post by teraflop »

el_benhameen wrote: post #25
nevi-me wrote: post #9

Reading this has reminded me of something I wanted to explore in the past. Most of my applications/requirements for a Pi include GSM, but I've found GSM modules to be very expensive, often being more expensive than the Pi itself. The author mentions a mobile USB modem, and it's just dawned on me that older 3G/HSDPA dongles are often very cheap. Does anyone have experience using them, especially what power implication…

This isn't an answer to your question, but can you tell me more about how you source your sims/data plans?

I investigated this a year or so ago for a hobby project. The best cheap option I found for non-trivial amounts of data in the US was T-Mobile's $10/month plan, which comes with 2GB/mo of high-speed data, and throttles down to roughly 64kbit/sec after that.

Re: Solar Powered Raspberry Pi Camera

#29

Post by oh_sigh »

el_benhameen wrote: post #25
nevi-me wrote: post #9

Reading this has reminded me of something I wanted to explore in the past. Most of my applications/requirements for a Pi include GSM, but I've found GSM modules to be very expensive, often being more expensive than the Pi itself. The author mentions a mobile USB modem, and it's just dawned on me that older 3G/HSDPA dongles are often very cheap. Does anyone have experience using them, especially what power implication…

This isn't an answer to your question, but can you tell me more about how you source your sims/data plans?

You probably want to look into M2M(machine to machine) plans if you don't plan on using standard telephone features with your device and just want data.

A lot of companies offer this service these days. For example(random googling first result): https://hologram.io/pricing/

is offering M2M sims for $1 per SIM per month + 40 cents per mb.

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