The original power supply was 12 volts at 2 amps (but I think those are Chinese Amps!). This variable zener changes the voltage. So the current will decrease to 1 Amp at the 24 volt setting. Any setting above the original 12 volts will deliver less current. Nice useful little video though.
Of course, since the basic power unit has not change therefore its total output watts will not change either, meaning if the voltage increases its amps should decrease accordingly, and vise versa.@@antoniodevincentiis3823
great potential project, but this mod will not drive this bulb for a long time without overheating and eventually damaging components ? i would be interesting to add power transistors to hold more power.
@@BlueScreendo There must be a zener diode on the feedback, otherwise it won't work. The idea is that we replaced the zener diode with a variable one (that i made ).
при выходе меньше 12вольт бп уйдет в релаксацию и под нагрузкой напряжение станет пульсирующим при выходе больше 20вольт под нагрузкой сгорит микросхема БП .
можно поподробнее почему будет пульсация, там же стоит конденсатор на выходе. и почему сгорит микросхема? вроде прикидывая в голове схему не пойму как может данная переделка на микросхему влиять? там же всего-то смещение напряжения на tl431, обратного напряжения на микросхему не поступает, почему она должна сгореть?
I Believe the rule of thumb is if the supply, in this case... 2 amps, and your device requires 3, the device load, it will not work fully or at all. Might damage the supply or the device because of a brown out/over current state that occurs when mismatched psu's are plugged in. If the device amperage is no higher than 2 amps, then the circuitry in the supply and the device with the correct voltage will regulate the amperage via the internal resistor set and how its configured in the regulator circuit. So just make sure your device has a supply at the voltage that is not a higher current rating than the device itself to avoid issues. Don't take my word for it, this is an educated guess. Have not messed around in over 2 decades with this stuff. Want to try to get back into it and this channel sure brings back alot of my training 30 years ago. Gotta brush up on the math again definitely! it explains it all period! Doing the math will definitely cue you in on the proper values. Ohms law should suffice. P.S. The Transformer secondary dictates the max current injected into the DC rectification/regulator circuit, and the entire output part of the circuit itself, is what regulates the output current. Why i suggested figuring out the math for the total resistance, and total voltage, employ ohms law, Voltage (v) divided by total resistance (r)...that will give you total current or amperes it will draw. (i) Good Luck!
If you increase voltage, obviously amperage will be decreased by the same factor(ideal condition), as a rule of thumb power remains constant. 12V X 2A = 24 Watts, You can take 24V but then ampere will be only 1A and so on...
@@asifsiddique6485 That rule applies to transformers only. What actually happens depends on the intelligence of the power supply. Generally the power that is requested depends on the load, but the device will probably have an overcurrent protection so may be automatically switched off if the current exceeds the rated value (2A in this case). Remember the original design of the device is for a fixed voltage (12V). It knows nothing about power, but if it is limited to 2A the power BECOMES limited to 24W. With the modification it will still be the same, it still knows nothing about power and is still limited at 2A. So if the load "asks" fo 2A it will attempt to deliver it as the current limit is not yet exceeded. And if the voltage is set to above 12V it will attempt to deliver above 24W. This means it will probably exceed power rating of its components, overheat and burn. So unless there is some extreme intelligence (unlikely) in this device it is up to the person that uses it to ensure that whatever load you plug into this modified PS it never consumes more that 24W, the device itself will not protect from such overload. So you have to be very cautious what you feed from the modified PS. Hope this makes sense :o)
Thankyou Walt P for the missing part just don’t want to look like a tube but we’re did the digi gadget come from ? What’s it’s part number and we’re do I stick it ?? Again I’m grateful for the speedy response
@@mickymannis He replaced the 470 mfd 16v capacitor at 1:25 with a 470 mfd 50v electrolytic capacitor. Be aware of polarity. Mark the negative (-) side before removing the old one. You can get all these parts at ebay, Amazon or any good electronics store. Hope this helps.
Boa tarde Gil e amigos. Creio ter assistido um vídeo em que se fazia um trabalho similar em uma fonte de notebook, de 19v, se não me engano. Creio que se o circuito for parecido, dá pra fazer. Forte abraço do Rio.
Muito bom o prejdto queria fazer um quais componentes usa e tem que subistiur o capacitor eu tenho a fonte está com esse capacitor estufado 6.8 uf 400v
@@littlepoison9632 а причем тут забор? зашел пернуть так подтверждай свои слова. автор регулирует точку опорного напряжения на тл431, по фидбеку увеличивает широту импульсов, поэтому растет выходное напряжение. понятно что при напряжении выше 12 вольт 2 ампер не будет, надо трансформатор перематывать, но напряжение регулируется. по сути это и есть принцип регулировки напряжения даже в статичном блоке питания, можешь из любого 12 вольтового 5 вольт сделать выставив правильные резисторы в делителе напряжения, как и из 5 вольтового 12 вольт
Не слишком маленькая механическая прочность у выводов, соединённых каплей припоя? Или это просто конструктор , которым нельзя пользоваться? Разве переменный резистор не должен быть многооборотным?
@@user-rk1el6vy9k Откуда такая информация? Приведите источник своих специальных знаний. Я давненько учился на "слесаря-сборщика РЭА", но помню, что "паяным соединениям противопоказаны механические нагрузки". Что-то изменилось с тех пор?
Я всё сделал точно также как на видео и у меня взорвался транзистор,так что это не грамотно показано, сначало нужно во всём разобраться и не подвергать людей риску смертельному,ради лайков,это жестоко.