A speaker/microphone/transmit button circuit for the puxing 777 which probably works for all puxing radios. I decided to reverse-engineering an earphone/microphone headset that came with the radio to determine how it worked. I can`t claim that I`m an expert in electronics theory, but I can say that I faithfully rebuilt the circuitry within the factory-shipped headset
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and it worked. The result allows me to leave my handheld radio in its charger while casually listening/transmitting with a button that I made instead of having to reach around and awkwardly squeeze the transmit button on the side of the radio. Once again, I built this circuit and it was successful for me, but there may still be a better way to do it. The microphone is a 20-cent electret microphone with no special modifications. The speaker I used is a standard 8ohm loudspeaker with no special modifications. The switch is a keyboard-style (push-to-talk) switch, and the capacitor I used is good for 10nF. If you have any ideas for improvements, let me know! I`ll post some photos once I have my completed little base station set up. My ultimate goal is to turn an el-cheapo handheld VHF radio into a decent desktop transceiver by combining it with a nice antenna (located on a balcony at 30ft) and a convenient, easy-to-use switches/buttons/microphone/speaker/etc on a desktop panel. Scott Harden has had a lifelong passion for computer programming and electrical engineering, and recently has become interested in its relationship with biomolecular sciences. He has run a personal website since he was 15, which has changed names from HardenTechnologies. com, to KnightHacker. com, to ScottIsHot. com, to its current SWHarden. com. Scott has been in college for 10 years, with 3 more years to go. He has an AA in Biology (Valencia...
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