Detecting Mobile Phone Transmissions With a Sound Card

Anyone who had a cheap set of computer speakers in the early 2000s has heard it – the rhythmic dit-da-dit-dit of a GSM phone pinging a cell tower once an hour or so. [153armstrong] has a write up on how to capture this on your computer. 

It’s incredibly simple to do – simply plug in a set of headphone to the sound card’s microphone jack, leave a mobile phone nearby, hit record, and wait. The headphone wire acts as an antenna, and when the phone transmits, it induces a current in the wire, which is picked up by the soundcard. …read more

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A Reproduction Vintage Sound Card

Before the AdLib sound card, sound on PCs was in a terrible shape. Since the dawn of IBM, all PCs included a speaker, but this PC speaker was only capable of sounding one note at a time. Chords on the PC speaker produced a weird ‘bubbling’ effect. Just a few years later, 8-bit sound could be created with the Covox Speech Thing, effectively a resistor ladder, with the parallel port on one side, and an 1/8″ plug on the other. These solutions for PC sound sucked.

It wasn’t until the first AdLib cards that superior sound showed up on the …read more

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