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    Will it effect laptop's battery if I use charger connected when fully charged?

    I have just bought a new Lenovo Laptop, IdeaPad-310. I think modern laptop / notebook has a overcharged controller that control charger when to charged and once battery fully charged, it should not charge the battery and laptop should take power from charger instead of battery to run. In system...
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    What would be the effect If I change 4700uF capacitor to 18000uF?

    I have an image of pcb. https://s15.postimg.org/66ipv52bv/20161205_134828.jpg I did not find a schematic of power supply in IC-STK4231 datasheet or for it in google search. I have a transformer to connect with this pcb ac input point, with output 35~AC, 7Amp.
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    What would be the effect If I change 4700uF capacitor to 18000uF?

    Thanks for your reply, I have not found a power supply circuit diagram for stk4231 on google search. STK 4231 ic datasheet also not containing details about power supply. I have just tried a circuit like Re: I am having problem with image upload in this thread, is showing a "X" icon. url to...
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    What would be the effect If I change 4700uF capacitor to 18000uF?

    Thanks a lot. I was thinking something like this. As it is too much 18000uF, it should effect. I have tried with this and found 2 skt4231 IC damaged. I think it was charged too high and after switching off, it was releasing charge to be discharged too long. I have not found a power supply...
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    What would be the effect If I change 4700uF capacitor to 18000uF?

    I have a dc bridge rectifier circuit to make ac to dc 50 volts output. It required two 4700uF capacitor, but I have 18000uF 70v in hand. If I use this 18000uF capacitor instead of 4700uF, will it damage my amplifier circuit- stk4231? Local electronic seller told that it will not effect if...
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    What can be happen if I use 10 inch 8-ohms speaker instead of 8 inch 8- ohms?

    Yes, but I think at this moment I have no choice- only to depend on the avilability in local market. :(
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    What can be happen if I use 10 inch 8-ohms speaker instead of 8 inch 8- ohms?

    Q1. If I use 10 inch instead of 8 inch speaker both having 8 ohms, will it decrease or increase sound quality? Q2. Currently I am using 8 inch 8-ohms speaker in stk4231 ic based sound system. Within 70% volume range it plays almost nice as I expected. But more than this voice seems clear- only...
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    Can it damage IC if connecting two speaker in parallel in output?

    Ok, I mentioned output voltage of my transformer + bridge rectifier. Sometimes it drops down to 50/49v to 51 to 52. I did not find a output voltage controller to make a fixed 51 volts as 7805 ic does output volts fixed to output 5volts. I found on net something lmxx ic to build a custom one. Is...
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    Can it damage IC if connecting two speaker in parallel in output?

    Yes, in parallel ohms will be reduced to 2.6 ohms. I did not run longer in parallel without confirmation, I think it did not damage. Re: I am sadly announcing that, I have lost one 8Ohoms speaker! :( you were right!!!, can you tell me why 8Ohms gone instead of 4Ohms speaker??
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    Can it damage IC if connecting two speaker in parallel in output?

    Yes, according to data-sheet, supply voltage is DC +/- 51volts.
  11. P

    Can it damage IC if connecting two speaker in parallel in output?

    I have just assembled a "STK 4231 ii" based amplifier unit what is 2 channel 100w stereo audio amplifier. I also have two 8ohm 8 inch speaker and two 4 ohms Speaker. If I connect two 8ohm in two output of my amplifier plays little noise - I think it is because speaker box vibrate much. But if...
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    Need to know pin out (input output voltage ) of an old UPS Transformer

    Dear 73's de Edd, You are right, It is very old I got this UPS around 2001/2002, I can not remember. I will check back again in my lab. Your information will help me too and I will check as you advised. Thanks for your help, I think I will be able to help my students in this case although I do...
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    Need to know pin out (input output voltage ) of an old UPS Transformer

    Dear Steve, I was trying these steps before posting this thread but was not sure. At that time I used 5v AC instead 12 v, what confused me that time is from one side To other I got very little change when I was expecting to get a major change as it shoud voltage step down or up! But thanks a lot...
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    Need to know pin out (input output voltage ) of an old UPS Transformer

    I have an old ups transformer, brand name is missing with ups cover box. This ups was operating in 220~230v input. I am uploading an image of this transformer, I need to know how to identify input voltage (primary cable) and output voltage ratings of other cables. Please help.
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