494
Item nr.
| Production | The Netherlands, 2019.
Price was 1 €. |
|---|---|
| Semi- conductors | PAM8403 Amplifier IC. |
| Cabinet | Pin box. Size 60x60x30mm. Weight 45gr. |
| Power | DC 5-6V. |
After the usual waiting period, my amplifier chassis, measuring 20x28mm (height 15mm) arrived, and could be built in. The chassis was 59cts, the speaker connectors were 15cts each, the knob 8cts, and the DC jack was 13cts, totalling the cost around 1.10 euro. The black audio cable was found in the dust storage, but probably cost more that the rest of the project! I later changed the audio cable from a fixed cable to a 3.5mm jack (another 10cts).
The name punaiseversterker arises from the Dutch punaise, meaning pin, and versterker, meaning amplifier. The energy efficiency of this amplifier is extreme. A conventional HiFi amplifier, as found in many living rooms, takes about 20W from the mains when switched on. The mini amp referred to above, is an order of magnitude more efficient, it takes about 2W. The PAM8403 module, supplied from a phone charger, consumes again an order of magnitude less energy, it takes just 0.2W from the mains.
| Obtained | 6/2019 from Home built. |
|---|---|
| Condition | 9. |
| Value (est.) | 2,2€. |
| Sound sample | PLAY SOUND The music played in my living is overheard in the attic at the sixth harmonic of the pulse frequency, around 1340kHz, on an Erres KY504. |
The board contains hardly more than the IC and a few smoothing and entry capacitors. The IC is rated at a switching frequency of 240kHz, but mine is a little lower, about 224kHz. I know, because the music I play is heard through the house on AM radio´s tuned at 224, 670, 895kHz, etc. Of course this points at a privacy problem with this amp (and my later PAM8403 amps); watch out what you watch and hear, because your neighbors might be listening in! This unit was used by my son until I made an amp with build-in bluetooth for him.