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|I have received a few emails asking for a transformerless power supply. Here is such a supply. This supply uses no heavy step down transformer and has an extremely low parts count. The circuit can be built very small and can supply small currents for small projects. The major downfall of this supply is that it is not isolated from the AC line and can only supply small currents.|
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|could this circuit be possible in a photo switch streetlights?|
|is it possible to connect an LM317 after the bridge rectifier for the transformerless power supply...like this one on your page?|
|1. Please indicate polarity of C1. All 400v capacitors i find are rated + and - on the pins. C2 polarity is clear. 2. I am trying to convert from 220v ac to 30v dc supply, can i use 30V rated Zener diode and 45v rated C2 ?????|
|I am searching for a transformerless power supply with high current rating. Output-12V,and high current rating|
|hi. is it safe if 10th std make this circuit and show its working for a science woking model fair.|
|i, I would like to know what would happen if (line voltage : 220 - 240 v 50 Hz) : 1 what modifications would be neccessary to protect the circuit conditions. Thank you!|
|hi, could you pls tell me how much voltage does this curcuit supply ? thanks|
|Hi, I would like to know what would happen if (line voltage : 220 - 240 v 50 Hz) : 1 The voltage drops to 120v 50Hz. 2 The circuit is switched on at line voltage 300v 50 Hz. what modifications would be neccessary to protect the circuit in both conditions. Thank you!|
|Build this power supply in a case|
|dear techineer, pls i would like to have detailed explanation on why each component is used esp. C1 and C2 thanks|
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