The frequency is set at 1K Hz, I use a mini transformer ( the input
has two wires and out put with 3 wires, input is 1 ohm and output 72
ohms, it appears like a cube measuring 1cmx1cmx1cm). As I need only
high voltage and low current, I drive the transformer direct from pin
3. I can measure output from pin 3 using a multitester, I connected a
LED to the output after a resistor it lights up.
Hope the above description helps....
Newbie
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Did you use a breadboard? If so, it's easier to troubleshoot. I'll
assume you can swap components easily.
At 1kHz you will not be able to see an LED turning on and off.
When you need to build a timer circuit at some frequency that is too
high for the naked eye to perceive, you have a couple of options.
One of my favorite tricks is to take a radio and set it to a blank
spot on the AM dial. If you hear a buzz on the radio when you turn
the 555 on, that means it's working.
Another way is to replace your timing cap with one that's big enough
to give you a frequency of about 10 Hz or 1 Hz, or something on that
order. If it makes an LED blink, you know it's working; then you can
swap the timing cap back to the design value, for 1kHz. You can be
pretty sure it will work with the new cap, since you didn't change
anything else.
Once you have made sure the timer is working, you can go on to the
rest of the circuit.
Possibly the one ohm primary of the transformer is too heavy a load
for the timer. Bogging the 555 down with such a heavy load might be
causing the output to malfunction. You may be able to improve
performance by putting some resistance in series with the transformer
primary. But I would be inclined to use a transistor to drive the
transformer.
