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  1. X

    LM317 Variable power supply

    one  quastion pls, is there a problem if I use 390ohm for R1 ? I use that rezistor because I have just a 10kohm potentiometer and a 2,2k one. I use r1=390ohm and r2=10kohm pot. Is that ok ? If I use the 2,2k pot, I must use aprox. 100ohm for R1, it will be ok a 100ohm/0,5W ?
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    LM317 Variable power supply

    ok thank you for answer but there sitll something that I dont like. I measure now the ripple on a 25ohm/18W rezistor with 20Vcc on it, riple was 20mV with 770mA trough the resistor. But when I rise the volotaje to 22 or more (25 is maxim with my 19vca traf) the riple was > 350mV. It seems...
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    LM317 Variable power supply

    ok I understand that but if I put a paralel tranzistor, short circuit protection is still active ? What can u tell me about ripple output rejection ? how can I measure that ? I set output for 3Vcc and conect an lihgt bulb who draw 530mA from 317. On the osciloscop I se an ondulation of 15mV. Is...
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    LM317 Variable power supply

    I just made the power suply with LM317 - TO220 and the multi-mmeter from the 0-30Vcc power suplply link. I want to know if I can put two LM317 in paralel for more curent, if I need it and how can I connect them, pin to pin or how ...
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    0-30 Vdc Stabilized Power Supply

    has someone redesign PCB for duble operational amplifier like MC34072 ? or even quad ? I can't find 34071 or TLE2141 in my place and OPA is to much expensive here ... but I have a few 34072 ...
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    0-30 Vdc Stabilized Power Supply

    I just find out about multimmeter with Atmega8 and I'll do soon. After that i find out about this 0-30vcc psu and I see that is perfect for mai multimmeter  :) but is something that i dont like : -with 24Vca transformer the Vcc result will be 34Vcc -D5-D6-C3-R3-D7 make a negative -5,6V power...
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