To brighten up those with radios with 4 batteries or more, here's the most economical of our suggestions: a single LED connected in series with the batteries, will flash at the same pace as the music. It is important to note that this LED will cause a voltage drop, on the order of 1.5 V, which will imply a small reduction in the volume of the receiver. However, if the reader usually does not use it to the maximum of its volume, he will not even notice this difference. We also observed that, in some radios, this reduction in the supply voltage can cause abnormalities of operation, in which case the system cannot be used. The reader should therefore experiment with the LED before attempting its final assembly, to see if the radio continues to function normally with this LED. When installing the LED, it is necessary to observe its polarity.
