Rogers postbag

Tell us about the cool things you've recently got
ag123
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Joined: Thu Jul 21, 2016 4:24 pm

Re: Rogers postbag

Post by ag123 » Fri Nov 24, 2017 2:41 pm

ahull wrote:
Fri Nov 24, 2017 2:36 pm
You wont get much revenue from me I'm afraid, my adblocker will bin the ads. :lol:
agree that google ads only pay tiny pennies, a lot of traffic generates only very little revenue, But if there is already quite significant traffic, it may make some difference, not too sure if that would be worth it though.

on a side note, i think stm32 duino along with the 3 different implementations is perhaps having a 'life' of its own. it is 'arduino flavoured' but in a sense, it is already doing things that some simplier arduino mcus won't (be able to) do (e.g. usb), and more importantly, i think it is getting noticed as a different 'new arduino' flavour

in a way this easily come pretty close to micro bit, less bluetooth and perhaps less some sensors (which may not be necessary except for relevant use cases)
https://en.wikipedia.org/wiki/Micro_Bit

stm32duino is realizing one thing i've always hoped to do, a self programmable usb device. it used to be that things are connected via rs232, back then it is simply 16450/16550 https://en.wikipedia.org/wiki/16550_UART. That's because vlsi / soc for usb is expensive (to the hobbyist / maker (a new term i guess with the arduino / 3d printing revolution)), stm32 duino with is origins in leaflabs maple is making all these possible, the 'old' rs232 style interfacing comes back to life in the usb age

in a way BP / MM is a present day 'swiss army knife' in which you can simply redefine its role by uploading a firmware, it has come so far ahead from the humble 'arduino' roots

interestingly and coincidentally back then bbc micro / arm started life in a way few noticed back then
https://en.wikipedia.org/wiki/BBC_Micro
today it seem like a replay of history with micro bit (and maybe arm cortex-m)
https://en.wikipedia.org/wiki/Micro_Bit
:lol:

i'd think usb would continue to stick around as usb devices can 'draw power from the port' alleviating the need for separate power sources

ag123
Posts: 810
Joined: Thu Jul 21, 2016 4:24 pm

Re: Rogers postbag

Post by ag123 » Fri Nov 24, 2017 3:55 pm

back on the topic of solar panel power supplies, other than lipo, would 'super capacitors' make any sense? :)
https://www.ebay.com/sch/i.html?_nkw=su ... r&_sacat=0
it is rather amazing to see capacitance in F or even hundreds of F, i'm used to seeing rather bulky caps that goes like 1000uf :lol:
apparently there are some inspirations like this
https://www.edn.com/design/power-manage ... harvesters

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RogerClark
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Re: Rogers postbag

Post by RogerClark » Fri Nov 24, 2017 9:03 pm

I don’t think Supercapacitors are cost effective, and most of them seem to be 2.7V so I would need 2 of them, and they are more expensive than LIPo for the same capacity

It’s probably better to buy a bigger solar panel


Re:Google Ads

LOL, I block thousands of add server urls at DNS level as well as running Adblock etc.

I also don’t run Google analytics on the sever, because I am not interested in the stats as it’s not a money making site.
And therefore I don’t give any info to google about who visits the site.

ag123
Posts: 810
Joined: Thu Jul 21, 2016 4:24 pm

Re: Rogers postbag

Post by ag123 » Sat Nov 25, 2017 3:19 am

i think one of the advantages of super capacitors is its rapid charging time, in that sense it would go from 0 to 2.7v much faster than do say a li-po cell.
i'm postulating that on cloudy days that may actually help, but i've not tried these out as well hence it is just a hypothesis
i've one of those 'lipo batteries + solar charger' 10000mah https://www.ebay.com/sch/i.html?_nkw=so ... y&_sacat=0
which i bought from a local retailer, i've left it at the window for more than a year, and the indicator lights never seem to reach full charge, i've not yet measured the voltages etc though
yup but for a supercapacitor it would take 2x 2.7v, but i'm thinking we can then have a LDO say lm1117 (an ams1117 it's there on Baite MM)
http://www.ti.com/lit/ds/symlink/lm1117.pdf
or better lp2950 (100ma rated)
http://www.ti.com/lit/ds/symlink/lp2951-n.pdf
https://www.ebay.com/sch/i.html?_nkw=lp2950&_sacat=0
hence, we'd be able to plug that 2x2.7v super cap into MM at the usb power inputs and have the board / stm32 powered

did a bit of google and found that there are various 'been there done that' articles
https://www.sensorsmag.com/components/u ... ess-sensor
https://www.google.com.sg/search?q=1f+s ... olar+panel
Last edited by ag123 on Sat Nov 25, 2017 8:30 am, edited 1 time in total.

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RogerClark
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Re: Rogers postbag

Post by RogerClark » Sat Nov 25, 2017 5:11 am

Aren't you just wasting the additional power by using a linear LDO regulator?

BTW, I tested those normal Buck converters from eBay but the efficiency is not that good when converting from 5V to 3.3V; probably around 80%

Re: Solar panel + battery

I would not trust the quality of the solar panel or the battery or anything else in those things

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