Hey AndrewT, yes this is true. The 20-0-20 was a deal I couldn't pass up. I can't justify dropping ~$60 for a new one. I'm still looking for one closer to spec but this one is what I have for now.
I'm thinking maybe a choke or two to drop some volts and maybe a couple of diodes as well. I realize diodes are not the most elegant way to do it but it's way less expensive than a new transformer. Thanks.
I'm thinking maybe a choke or two to drop some volts and maybe a couple of diodes as well. I realize diodes are not the most elegant way to do it but it's way less expensive than a new transformer. Thanks.
As you already know, the best thing to do is get a transformer with the proper voltage.
The most efficient way to drop voltage is with a buck regulator... but there isn't much point in using a linear regulator then. You could use one linear regulator to drop some voltage then a second one to give you your output voltage. A diode or two also has the added benefit of reverse polarity protection.
The most efficient way to drop voltage is with a buck regulator... but there isn't much point in using a linear regulator then. You could use one linear regulator to drop some voltage then a second one to give you your output voltage. A diode or two also has the added benefit of reverse polarity protection.
You can always just ues a beefy npn transistor with a zener reference to drop some voltage too. That's what I meant by using two linear regulators.
I would use a diode to drop a volt and provide some reverse polarity protection, connected to the collector of an npn transistor. Connect a resistor between the collector and the base of that transistor. Then connect an appropriately rated zener diode from the base of the transistor to ground. You have to size the resistor so that the transistor has enough base current to ensure adequate emitter current for you application. You also need to choose a zener with a high enough power rating.
I would use a diode to drop a volt and provide some reverse polarity protection, connected to the collector of an npn transistor. Connect a resistor between the collector and the base of that transistor. Then connect an appropriately rated zener diode from the base of the transistor to ground. You have to size the resistor so that the transistor has enough base current to ensure adequate emitter current for you application. You also need to choose a zener with a high enough power rating.
Hi guys
Im building a similar supply on a breadboard, i have difficulty in measuring the output current. Do i need a load(shunt resistor) to be able to measure my output current. when i measure the output voltage i get required values. when simulating the multimeter reading at my output is very very small (the current). need help urgently. thanx
Im building a similar supply on a breadboard, i have difficulty in measuring the output current. Do i need a load(shunt resistor) to be able to measure my output current. when i measure the output voltage i get required values. when simulating the multimeter reading at my output is very very small (the current). need help urgently. thanx
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