Larger solar panels require charging circuitry to regulate the charge current and protect the battery from overcharging. Our solar panel is small enough that a charge controller isn't required.
The battery and solar panel are removable so that you can remove the battery and solar panel and set them outside to charge with less concern for the weather and theft. You could also have two batteries and have one charging outside, while you use the boombox inside, or in shade.
Batteries will last longer if kept in a charged state.
Try to keep lead acid (SLA) batteries fully charged, and never allow voltage to fall below around 9.6 volts (The amp will stop working at around this voltage)
NIMH batteries can be fully discharged without damage, but also should be kept charged for best results.
If your battery will not be used for a while, its charge should be topped off periodically, either by leaving in a sunny spot with the solar panel attached, or by using a wall charger.
I would do this monthly with a SLA battery, and biweekly with NIMH.
Read this instructable
for some basic solar battery charging information.
Putting a bead of silicone caulk around the glass on your solar panel is recommended to help weatherproof it.
Different audio sources have different output levels. If you feel your box is too quiet, the source may not put out strong enough of a signal.
You should be able to turn the amplifier nearly all the way up, and control the volume with your source, assuming it has a volume control. You can experiment with different combinations with the two volumes in order to get the best sound.
Keep the solar panel oriented towards the sun, and not shaded for best charging. Even a small amount of shade negates its ability to charge the battery.
I get 6 hours playback from a fully charged 2.6 Ah battery at top volume, and 10+ hours at normal listening volumes. This is with the solar panel disconnected. YMMVSonic Impact amp specs-
The TA2024 is a 15 W/ch continuous average two-channel Class-T Digital Audio
Power Amplifier IC using proprietary Digital Power ProcessingÃ¢ï¿½Â¢ technology.
Class-T amplifiers offer both the audio fidelity of Class-A/B and the
power efficiency of ClassÃ¢â�¬â€�D amplifiers.
Ã�Â· Battery Powered System
Ã�Â· Optional AC Adapter for 12V DC power source
Ã�Â· No heat sink required up to 15W per channel
Ã�Â· Intelligent short circuit protection
Ã�Â· Connects to any passive 4/8 Ohm speakers
Ã�Â· Takes standard audio line input from any sound system
Ã�Â· Fully integrated solution with FETs
Ã�Â· Easier to design-in than Class-D
Ã�Â· Reduced system cost with no heat sink
Ã�Â· Dramatically improves efficiency versus Class-AB
Ã�Â· Signal fidelity equal to high quality linear amplifiers
Ã�Â· Class-T architecture
Ã�Â· Single Supply Operation
Ã�Â· Ã¢â�¬ï¿½AudiophileÃ¢â�¬ï¿½ Quality Sound
0.04% THD+N @ 9W, 4 Ohm
0.18% IHF-IM @ 1W, 4 Ohm
11W @ 4 Ohm, 0.1% THD+N
6W @ 8 Ohm, 0.1% THD+N
Ã�Â· High Power
15W @ 4 Ohm, 10% THD+N
10W @ 8 Ohm, 10% THD+N
Ã�Â· High Efficiency
81% @ 15W, 4 Ohm
88% @ 10W, 8 Ohm
Ã�Â· Dynamic Range = 102 dB
Ã�Â· Mute and Sleep inputs
Ã�Â· Turn-on & turn-off pop suppression
Ã�Â· Over-current protection
Ã�Â· Over-temperature protectionHarbor Freight solar panel specs
22.5 VDC open circuit voltage
14.75"L x 6.5"W x .875"Thick
weather, shock, rust, UV resistant frame