Because the tangled messy long wires on a breadboard pickup all kinds of garbage.I am trying to find out if we are picking up a radio station on the long wires.
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Because the tangled messy long wires on a breadboard pickup all kinds of garbage.I am trying to find out if we are picking up a radio station on the long wires.
Because the tangled messy long wires on a breadboard pickup all kinds of garbage.
The wires of your breadboard are too long and have series inductance. If you used a small compact pcb like all REAL circuits then maybe adding a 0.1uF ceramic disc capacitor with short leads to the output and ground (like in the datasheet) will kill the oscillation.What are your thoughts?M
The wires of your breadboard are too long and have series inductance. If you used a small compact pcb like all REAL circuits then maybe adding a 0.1uF ceramic disc capacitor with short leads to the output and ground (like in the datasheet) will kill the oscillation.
I noticed by placing a capacitator between the emitter of the transistor and GND, the ac is gone. Why did we not suggest this this initially?
Because you've never posted the actual schematic, despite been asked to.
It's possible you have a faulty transistor and the collector-base junction is breaking down.Before I connect the lead to the collector of the npn transistor, i only get 5V from 7805 via the base. Once i connect the main current to the collector, I get this AC current.
I am sorry, being inexperienced I thought the one I posted was good enough. I will be more detailed in the future.
I have looked at the datasheet several times, I must be overlooking something. Please tell me what that is.
I looked at www.datasheetarchive.com and found 48 datasheets. the Fairchild datasheet has these two high current circuits:I have looked at the datasheet several times, I must be overlooking something. Please tell me what that is.
Adding a darlington transistor between the 7805 and gate of the power transistor solved the problem. Anyone have a clue as to why? Thanks.M
so according to a data sheet for the 7805, you should have small (1-10uf) bypass caps between the input pin and the ground pin, and from the output pin to the ground pin. you should also have the 7805 heat sinked because of the huge amount of voltage drop from 24 to 5 volts.
if you are going to use regulators and other analog chips, you should read the data sheet first. go to www.datasheetarchive.com and put in the part number you want a datasheet for
The calculation for the heating is simple: Volts x Amps= Watts.The regulator doesn't get hot, so I didn't use a heat sink.