Thanks infinia. Yes but this seller seems honest. I see other that later
first some few thing i want make sure that i know:
If i use a transformer that example +30-0-30+ 3A to connect to this board will What will be the +VCC and -VCC voltage will it be +/-60 or +/-30?
first some few thing i want make sure that i know:
If i use a transformer that example +30-0-30+ 3A to connect to this board will What will be the +VCC and -VCC voltage will it be +/-60 or +/-30?
assuming the XFMR tested 30V + 30V at 3A at your line voltage, using 1 full wave bridge rectifier.
The bulk capacitors charge to peak rectified voltage minus 1 diode drop.
30V RMS*1.414-0.8V = 41.6V with the opposite polarity on the other side.
could provide about 90W into 8 ohms but not double into 4 ohm load with this 180VA transformer.
The bulk capacitors charge to peak rectified voltage minus 1 diode drop.
30V RMS*1.414-0.8V = 41.6V with the opposite polarity on the other side.
could provide about 90W into 8 ohms but not double into 4 ohm load with this 180VA transformer.
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You sure about that?
So 1 watt is not 1 Va watt? I think could because in music it is not continuous like in testing that use waves stress that heat up faster the transformer? So if i use waves stress then 2 waves watt will use 2 Va right?
How much transformer side do i need? Should i use dual output +55-0-55+ 8A transformer or Single out transformer that is 110v 8A?
Thanks so its 41.6V for dual 30v power supply.
What if iuse a Single output transformer 110v 8A what will be the +/-VCC?
The transformer side should be specified by your seller or amp instructions.
Trandformer drops the voltage, although the total power of the trans still applies.
Tat would mean the more power you have the more current can flow throw at the specified voltage
Getting back to amplifier context. I have found the CMoy Build article
Which can give you some idea on basic schematic and parameters.
There is a link to free Teas Instruments book on Amps is is very useful too Op Amps for everyone
It is available for free, if the link does not work you can search Internet. It will give you the idea on Vcc and other concepts used in Amp.
You would be having Transformer secondaries to power your circuit.
Than inside the circuit when you implement the op amp unit it will have a number of pins, one of it is powered by so called Vcc. You will not be getting it directly from the trans. And most likely the value would be much lower than from the trans secondaries, meaning you will need to use a circuit and ohms law to reduce the voltage from trans secondaries to the Vcc one.
Go through the book, you will get lots of questions closed than.
Trandformer drops the voltage, although the total power of the trans still applies.
Tat would mean the more power you have the more current can flow throw at the specified voltage
Getting back to amplifier context. I have found the CMoy Build article
Which can give you some idea on basic schematic and parameters.
There is a link to free Teas Instruments book on Amps is is very useful too Op Amps for everyone
It is available for free, if the link does not work you can search Internet. It will give you the idea on Vcc and other concepts used in Amp.
You would be having Transformer secondaries to power your circuit.
Than inside the circuit when you implement the op amp unit it will have a number of pins, one of it is powered by so called Vcc. You will not be getting it directly from the trans. And most likely the value would be much lower than from the trans secondaries, meaning you will need to use a circuit and ohms law to reduce the voltage from trans secondaries to the Vcc one.
Go through the book, you will get lots of questions closed than.
yes dual secondary provides +/-
single " provides only +
most class AB amps use +/- supplies
900VA step down transformer 110V * 1.414 - 2(0.8)= +154 VDC at 8A
do not use this transformer for beginner amplifiers!
your other 180VA will be perfect to built a pair of 150W amplifier boards
it might be useful to power the larger kit amps too,
but it can only support limited continuous power until the output voltage starts drooping and the windings get hot.
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Thanks again
About Filtering board
So if a filtering board uses 4x10000uf 100v what dual output transformer the max u can use?
voltage wise you don't want to exceed those bulk capacitor rating under worst case conditions> which is high line* and unloaded* conditions.
high line* is the variation of the mains voltage from the utilities provider at your location. can measure at off peak hours at the wall socket.
unloaded* refers to the transformer nominal ratings and regulation. so if the transformer secondary voltage is spec'd at full load then the voltage rises with no load. depends on many factors toxoid cores can be 3-5% and EI cores can be twice as high 6%-10%.
so roughly without any data (100 VDC / 1.414) -5% ~ 67-0-67 V RMS
consider going lower if you don't have test conditions of the transformer, otherwise the capacitors can be at some risk.
high line* is the variation of the mains voltage from the utilities provider at your location. can measure at off peak hours at the wall socket.
unloaded* refers to the transformer nominal ratings and regulation. so if the transformer secondary voltage is spec'd at full load then the voltage rises with no load. depends on many factors toxoid cores can be 3-5% and EI cores can be twice as high 6%-10%.
so roughly without any data (100 VDC / 1.414) -5% ~ 67-0-67 V RMS
consider going lower if you don't have test conditions of the transformer, otherwise the capacitors can be at some risk.
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