3 ms·
Could this idea be used, for example, to power a landline phone like it was done with POTS? So no external power was needed for the phone and it even worked in
by severino 3y ago
Could this idea be used, for example, to power a landline phone like it was done with POTS? So no external power was needed for the phone and it even worked in the event of a blackout.
- masklinn 3y agoAccording to SIN 352[0] > the average DC current in the loop and voltage across the phone will be up to 42 mA at 12.5 V (short line), up to 33.5 mA at 10 V, and will be not less than 25 mA at 9 V. So it's around the same values. However the distances are in a different realm entirely: the spec sheet tests over 30m of fiber, phone loops range in kilometers. [0]: https://www.openreach.co.uk/cpportal/content/dam/cpportal/public/images-and-documents/home/help-and-support/sins/documents/SIN_352.pdf https://www.openreach.co.uk/cpportal/content/dam/cpportal/pu...
- rwmj 3y agoHmm, a class 4 laser going into a consumer landline phone, what could possibly go wrong?
- gosub100 3y agoit could be done safely with an interlock on the data side. if it doesn't get a ping every 1ms it cuts power.
- chx 3y agoSure thing. This is 540mW and looking at https://electronics.stackexchange.com/a/36495/27147 https://electronics.stackexchange.com/a/36495/27147 > headphone jacks typically provide only 10-20 mW of output power. microphones draw even less. A handful of mW is plenty to drive even an ARM Cortex M0 not that you need something that complex.