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  1. WHONOES

    Astable 555 500Khz 20ms

    Ha Ha.
  2. WHONOES

    Astable 555 500Khz 20ms

    Yup, you are right. At 500Khz square wave, the harmonics will extend high into the MHz region. Didn't know it was the International distress frequency. We learn something every day eh.
  3. WHONOES

    Searching for small load cell or method for measuring forces in the 1 g (10mN) range

    You could do your measurement mechanically using a gram force gauge. I found some that start at 0.3 to 3grams full scale. See the link below. http://www.wagnerinstruments.com/products/force-gages/mechanical-force-gages/gram-dial-gd
  4. WHONOES

    Astable 555 500Khz 20ms

    What are you trying to do with the coil. Are you asking about a power supply for the circuit? Why do you think you need diodes in your circuit?
  5. WHONOES

    Astable 555 500Khz 20ms

    BTW, the simulation was performed on Simetrix which is I think the best of the bunch.
  6. WHONOES

    Astable 555 500Khz 20ms

    Try the attached circuit. It uses a 4093 which is a Schmitted 2 input Nor gate. The first stage produces the 500KHz whilst the second stage produces 50Hz pulses. The Second stage is used to gate the first stage on and off giving you 500KHz pulsed at 50Hz. The pulses of both sections will have as...
  7. WHONOES

    12 / 24 or 48v to 400V Boost Converter to charge electric car from solar panels

    Alec T is correct. You will need to profile the charge regime. Just pumping current into a set of batteries is not safe. But, presumably if you are as you say, charging batteries in your car, the charging circuits contained therein will take care of the charge profile. Designing a switch mode...
  8. WHONOES

    12 / 24 or 48v to 400V Boost Converter to charge electric car from solar panels

    Hi. Sorry about the short delay. I had to rummage through a large number of simulations to find the attached circuit for an 800V generator showing the basics.
  9. WHONOES

    12 / 24 or 48v to 400V Boost Converter to charge electric car from solar panels

    If you are going to have a play with this idea, I would transformer couple the output . I have used the 555 for similar circuits and it works quite well. Its control pin can be used to provide feedback to control the O/P volts by altering the PWM mark space.
  10. WHONOES

    Problem with inductive load

    I see it is a Radio control servo. These don't normally require supply de-coupling though adding some will not hurt. To drive from 3.3V, the most you will need is a level shifter which is dead simple needing just one transistor and 2 resistors. As suggested by Harald Kapp, you will need to...
  11. WHONOES

    Common Emitter Amplifier - Class B

    It's still class A though.
  12. WHONOES

    Current passed through my headphones into my head? Is it possible?

    Can't do anything about tinnitus, you just have to learn to put up with it. You learn to ignore it after a while.
  13. WHONOES

    Charging a V-mount battery 2A, what charger?

    Working current and charge current are 2 different things. The charging regime depends on the chemistry of the battery. It seems to be a LiPo but that is net entirely clear.
  14. WHONOES

    Common Emitter Amplifier - Class B

    If the amp is biased to have a dc current flowing through it, it is class A.
  15. WHONOES

    isolating transformer and variac - what order?

    I agree with your reasoning.
  16. WHONOES

    Help request for a switching design

    Not a lot different to your original post. Try drawing more detail on how you want to switch. As presented, we have no idea which is to be a current measurement and which is to be a voltage. Also,do you want to use a mechanical switch, rotary or otherwise or, do it all automatically? Much, much...
  17. WHONOES

    Help me please to get a good night's sleep!

    My Brother-in-Law suffers with sleep apnoea and uses a mask at night which has largely cured the problem. I would suggest that you see your Doctor and explain your problems as there may be a solution. I don't think a DIY solution is appropriate or safe.
  18. WHONOES

    Help request for a switching design

    I take it you mean millivolts (mV) and milliamps (mA). A schematic of some description would be of enormous help to us so that we can help you otherwise we are just making stabs in the dark. The process of putting down on paper in the form of a sketch what you are trying to do can often suggest...
  19. WHONOES

    Help request for a switching design

    What values of Voltage and Current are you expecting to measure.
  20. WHONOES

    Where to add dimmer in ac led bulb?

    The simple way to dim LED's is with PWM (Pulse Width Modulation).
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