The infinity bug is connected across the phone-line of a distant phone in parallel mode. It uses surface-mount resistors, capacitors, transistors and diodes. It gets operating current from the phone line (leech device), no external power supply is required.
This circuit allows you to transform a mains adapter in to a charger for NiCd – NiMH batteries. With selectable charge current (50mA-400mA), the charger can be used to charge cellular phone, toys, portables gadget, video batteries, MP3 players etc. Supply voltage input starting from 6.5VDC to 21VDC (depending on used battery). The circuit [...]
This VHF TV TRANSMITTER can be used to transmit movies from your PC to your living room, run a college TV station, hotel cable system info pages, re-transmit the TV program you’ve never been able to receive in your valley, cover rural areas of Africa with TV signal from satellite stations and other system that [...]
This project can transmits phone conversation up to 30 metres (100 feet) to an ordinary FM receiver. You can experiment to get greater transmission range away from the phone line by adding an aerial (about 150 cm of 26 gauge wire) to the collector of T2 (see circuit below).
To use phone transmitter, you need to [...]
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