Solar Powered Audio Player

Sensors Sound & Audio
1

Hello-

I am trying to make the smallest footprint audio player that would:

  1. be solar powered

  2. Have enough amps to power a 4ohm 24W transducer/exciter.

  3. not need a trigger to play continuously

I have bought the Little Soundie, the Noisy Cricket and a 6w solar panel.

But I am running into a few problems.

  1. I am not sure that the one 6w solar panel would be enough to power both the Little Soundie and the Noisy Cricket.

  2. is the power from the solar panel stable enough for these devices?

  3. would I be better served charging a battery then letting that battery run the devices?

  4. is there a better player, idea or solution that I should try?

Really appreciate any feedback or help. Thanks so much,

2

Hi jutboyd,

A battery powered solution is probably the best here since solar power can fluctuate wildly depending on a lot of factors. A single-cell Lithium-Ion battery will work well to power both the Little Soundie and Noisy Cricket. In order to choose the right capacity of battery, you will want to test to see what kind of current draw you get with both powered up and playing sound.

The [SparkFun Sunny Buddy will work with your 6W Solar Panel to charge an attached battery. You can even set it up to have your load attached with the battery and solar panel so everything can stay in the same circuit without having to remove the battery for either powering the Little Soundie + Noisy Cricket or charging. If you want to learn more about how the Sunny Buddy works and how to set it up, I would recommend reading through our [Hookup Guide.

I hope this helps you get started figuring out a way to build this project. Let us know if you have any other questions about these products and we would be happy to help as much as we can.](Sunny Buddy Solar Charger V13 Hookup Guide - SparkFun Learn)](https://www.sparkfun.com/products/12885)

3

Hi TS-Mark-

Thanks for the reply. I am about to ask very dumb questions, I apologize in advance. Looking at the Little Soundie I see it needs power between 3.3v-5.5v, and the Noisy Cricket needs 2.4-5.5VDC, would it be best to buy power supplies for each so that I can test the current draw? Also, I have been looking specifically on a tutorial on current draw but haven’t found one that would help this novice use their multimeter to test current draw.

I can buy the power supplies, but was hoping not to needlessly buy powersupplies just to test the current draw, to then power it from the solar panel.

I like your recomendation for the Sunny Buddy and will order that as soon as I see if I need to order more things to figure out how much current is being drawn. Thanks again, really appreciate it.

4

One more quick question. Another scenario would be to use a microphone into an external audio effect then out to the Noisy Cricket then to a transducer, would you recommend your electret mic for such a use?

5

Hi again,

Since the input voltage ranges for both boards overlap a bit, you can use, say, a 5V DC or 3.3V power supply for both the Little Soundie and Noisy Cricket to test. There is no need to have separate supplies for them unless you specifically want to split it for some reason.

To measure current, you need to measure in-line on the circuit. The [Measuring Current section of our “How to Use a Multimeter” tutorial covers this fairly thoroughly. It might be a bit tricky if you do not have something like the [Banana to Alligator Cables like we use in that tutorial but you can get by with your standard multimeter probes by wrapping some wire around them as well. There are also other options like this [Current and Voltage Sensor for more in-depth monitoring of a circuit’s power draw.

As for adding a mic to this circuit, the [Electret Mic Breakout could work but the audio output needs to be processed and amplified as it’s really just an analog voltage and is best used for measuring the intensity/“loudness” of sound and not as a true microphone. [This tutorial might give you a good idea of what type of components you would need to use to process the output of the microphone.](Vox Imperium: Stormtrooper Voice Changer - SparkFun Learn)](SparkFun Electret Microphone Breakout - BOB-12758 - SparkFun Electronics)](Zio Current and Voltage Sensor - INA219 (Qwiic) - SEN-15176 - SparkFun Electronics)](Banana to Alligator Cable - CAB-00509 - SparkFun Electronics)](How to Use a Multimeter - SparkFun Learn)