Hi lovely All About Circuit Community,
This is my first post, so I'm new to this super community and also pretty new to electronics. So please don't be too harsh on me.
About my litte project:
I'm trying to build a solar powered audio amplifier. It should also include batteries, so i can keep listening even after the sun went down.
So far I have build (with the help of Instructables and Co.) an audio amplifier based on the LM386 (see the green part in the schematic below). It works fine during daytime, when I plug the solar panel straight to the amplifier. But of course, as soon as the sun is gone, the sound is gone as well. That's why I'm trying to include some batteries, which should be charged while the sun is up and when the sun went down the batteries should be used as power supply for the amplifier (see the red part in the schematic below).
So far I read quite a bit about charging batteries and pretty much everywhere is written that it's a really difficult topic and you should rather just buy a quickcharger, instead of making your own. That's probably true, but I would like to build my own anyway, because I want to understand what's going on. I'm also aware of the fact that "my" charger won't be as efficient or good for the batteries as one you buy, but at least I made it myself.
I made my plan for the charger based on the "Solar Charger Circuit" from http://electroschematics.com/4746/solar-charger-circuit/ . I pretty much just changed the values.
The plan is to use 5 x AA batteries, which should have a voltage of around 6V if connected in series. I read that you can charge a AA battery with 1,6V and around 0.2C. Assuming that my batteries gonna have a capacity of 1200mAh, I could charge them with 240mA and 8V (5x1.6V). To achieve the 240mA the resistor R5 needs a resistance of 33Ohm and the 8V can be achieved by adjusting the LM317. When the batteries are fully charged they'll have a voltage of >6.2V and the Zener-diode will conduct and provide base current to T1, which will then ground the ouput of the LM317.
Would this more or less work or am I totally wrong? Sorry, but I'm quite new to electronics.
Thank you so much for any response.
This is my first post, so I'm new to this super community and also pretty new to electronics. So please don't be too harsh on me.
About my litte project:
I'm trying to build a solar powered audio amplifier. It should also include batteries, so i can keep listening even after the sun went down.
So far I have build (with the help of Instructables and Co.) an audio amplifier based on the LM386 (see the green part in the schematic below). It works fine during daytime, when I plug the solar panel straight to the amplifier. But of course, as soon as the sun is gone, the sound is gone as well. That's why I'm trying to include some batteries, which should be charged while the sun is up and when the sun went down the batteries should be used as power supply for the amplifier (see the red part in the schematic below).
So far I read quite a bit about charging batteries and pretty much everywhere is written that it's a really difficult topic and you should rather just buy a quickcharger, instead of making your own. That's probably true, but I would like to build my own anyway, because I want to understand what's going on. I'm also aware of the fact that "my" charger won't be as efficient or good for the batteries as one you buy, but at least I made it myself.
I made my plan for the charger based on the "Solar Charger Circuit" from http://electroschematics.com/4746/solar-charger-circuit/ . I pretty much just changed the values.
The plan is to use 5 x AA batteries, which should have a voltage of around 6V if connected in series. I read that you can charge a AA battery with 1,6V and around 0.2C. Assuming that my batteries gonna have a capacity of 1200mAh, I could charge them with 240mA and 8V (5x1.6V). To achieve the 240mA the resistor R5 needs a resistance of 33Ohm and the 8V can be achieved by adjusting the LM317. When the batteries are fully charged they'll have a voltage of >6.2V and the Zener-diode will conduct and provide base current to T1, which will then ground the ouput of the LM317.
Would this more or less work or am I totally wrong? Sorry, but I'm quite new to electronics.
Thank you so much for any response.
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