Cekpi7

Cut off voltage is set by zener diode, check voltage on diode. Also check voltage on 4.7K resistor

For testing 12V battery and 5A psu should be more than enough (which is what i use), for listening however you would need way more than 100W panel, class AB amps can draw 20-30W just by sitting idle, my 2kW ground zero amplifier draws 20W at idle and it's class D. If you have 2 amps (one for sub, one for mids-higs) that would draw as much as panel would put out during cloudy day.100Ah battery would help with high current draw but SMPS PSU is best option, or high current 12V charger like CTEK makes but those are really expensive.

This doesn't make sense to me but i'm gonna try it, i have grounding bracelet and i'm gonna bridge that 1M resistor in it. Can't really get good sleep recently so i got nothing to lose :).

Yeah, i was thinking about yellow but wrote orange for some reason.My idea was like GoryashchiyeKlyuchi's design but with plastic instead of epoxy.I don't like look of naked led display.

Yeah, i was thinking about yellow but wrote orange for some reason.My idea was like GoryashchiyeKlyuchi's design but with plastic instead of epoxy.For some reason i don't like look of naked led display.

You can connect it to digital pin and turn it on for a 1-2ms which is enough for arduino to read moisture, this way there was lot less corrosion.

Would be cool if you could get orange leds or put some sort of filter in front of red ones and fake glass so it would look like nixie tubes.

Depending on power of amplifier and power supplies. You can always turn down gain on amplifier.

50-60A psu should work fine with 300W class D amp. As a good rule of thumb you should get psu that can produce same or higher current than fuses can take (usually 30-40A on 300W amp). Car batteries are usually made just to start car and not really for discharging them completely so if you would go that route you should use deep cycle battery. Constant trickle charge is not good, with open batteries it will produce a lot of hydrogen and that won't be good if you use it indoors, SLA on the other hand might lose some of acid (due to evaporation) and since they are closed you can't add it (you can but it's a bit more complicated).

You are partly right, this isn't ideal setup.Since TP4056 can only supply 1A to 18650 that means that you simply can't get more than 3-4W of constant power but you can get a bit higher peak (5-6W). There is also a problem with charging and powering router at the same time since when there is power loss and your power turns back on you are gonna have to recharge battery and power your router for that period so you might get only 2-3W of usable output. Some routers can work with really low power (12V 100mA = 1.2W) but for some of them this might be problem.

You should use diode like shown on schematics and explained in step 4 since you can burn some PSUs by feeding 12V to their output. There is a chance of overcharging your batteries if you have PSU that can deliver more than 14V so it's good idea to use switch to turn off psu, in case you are listening at higher levels you are gonna ask for a lot of current from battery so there is very small chance of actually overcharging battery. Alternative is to set PSU to 13-13.5V since this is safe voltage to let your battery sit at or even get charge controller.

Yes, it can be charged on any usb port (5V, at least 500mA)

Where did you buy enclosure? I really like how you made things, however you should put heatsink on chip, even small one. You have a lot of room in your enclosure so it shouldn't be the problem.

Thanks for information, sadly i don't think removing picture will do anything since you can clearly see that ring back on every picture in next step. Most of the times that paper ring is not holding on cell with glue so it will fall off, this is just precaution to not throw it away or forget about it. I am however gonna bold those important things and add warning.

Thanks for information, sadly i don't think removing picture will do anything since you can clearly see that ring back on every picture in next step. Most of the times that paper ring is not holding on cell with glue so it will fall off, this is just precaution to not throw it away or forget about it. I am however gonna bold those important thing and add warning.

These are all basic things, not really worth mentioning.Congrats on your first instructable though.

Agree, but when you have a lot of power and much bigger system than stock then you want something like DSP to take care of it all. You don't really want to blow your 1000$ tweeters because you ran them too low.