497
Item nr.
Solar panels in frame.
| Production | The Netherlands, 2019.
Price was 4.10. |
|---|---|
| Cabinet | Photo frame. |
| Power | 5V. |
| Obtained | 8/2019 from Home built. |
|---|---|
| Condition | 8. |
| Disposed | Storage (inquire if interested to buy). |
The picture left shows front and back of the solar panels and the power cable with 3.5mm plug and DC plug. The panel unit has a 3.5mm jack. Both panels have their minus connected to the shaft (ground). 
The plus of the panels are tip and ring, so with a suitable cable the two panels can be used separately. The cable I made connects the two panels in the DC plug at the end. Connections are all made at the back of the photo frame. As each panel is rated at 5V 1.25W, it is no surprise that under full sunlight there is enough power for moderate listening. Still, an experiment like this has some uncertainties (well, all experiments have, otherwise they would not be experiments, would they?). One uncertainty is how power degrades under decreasing light conditions. The other is how the amp behaves under low power conditions, and here appears to be the main problem. When power decreases, the PAM8403 integrated amplifier produces a motorboat like rattle. This makes the amps utterly unsuited for PV supply. For feeding a Grundig radio (during daytime), the panel unit is fine. For more serious use, it must be combined with an energy storage system.