Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here:
https://overunity.com/5553/privacy-policy/
If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding

User Menu

Custom Search

Author Topic: Simplest oscillators for DC  (Read 19080 times)

Belfior

  • Hero Member
  • *****
  • Posts: 534
Re: Simplest oscillators for DC
« Reply #45 on: January 23, 2019, 02:15:28 PM »
This would give at least kilohertz

https://www.youtube.com/watch?v=I24nDi_q-EU

reed switch that stays open until the cap is charged and then it dumps, when the current stops flowing

Bob Smith

  • Hero Member
  • *****
  • Posts: 733
Re: Simplest oscillators for DC
« Reply #46 on: January 23, 2019, 06:57:07 PM »
How fast can we switch with a relay so that it won't break in few hours?

The simplest solution so far has been a BJT in reverse avalance so the base is hanging. I think it needs something inductive on the secondary side and not just an LED to work though.

I have also seen 2 mosfets connected to a battery and switching. Can't find the video anymore
What I've found with the reverse wired relays is that they self-oscillate at a fairly low frequency. That can be played with a bit with resistors. The smaller relays seem to run faster. But as you say, wear and tear seems to have its effect on them. I believe the internal arcing also wears away at the contacts after a while, at least from what I've seen when running them for extended lengths of time. The trick might be to run the DPDT relay at the lowest possible power.  I've run them off small (5w?) solar panels.

Bob Smith

  • Hero Member
  • *****
  • Posts: 733
Re: Simplest oscillators for DC
« Reply #47 on: January 23, 2019, 06:58:31 PM »
Question:
Is a tank circuit (simple L-C) an oscillator if the cap is discharging  and the inductor is powered by ambient energy?
Bob

Belfior

  • Hero Member
  • *****
  • Posts: 534
Re: Simplest oscillators for DC
« Reply #48 on: January 23, 2019, 08:25:19 PM »
Question:
Is a tank circuit (simple L-C) an oscillator if the cap is discharging  and the inductor is powered by ambient energy?
Bob

Well it must be, but how much ambient can you get?


Bob Smith

  • Hero Member
  • *****
  • Posts: 733
Re: Simplest oscillators for DC
« Reply #49 on: January 26, 2019, 05:16:57 AM »


Quote from: Bob Smith on January 23, 2019, 06:58:31 PMQuestion:
Is a tank circuit (simple L-C) an oscillator if the cap is discharging  and the inductor is powered by ambient energy?
Bob
[/font]

Well it must be, but how much ambient can you get?

Probably not more than a few millivolts. But with the low millivolts, to get a tank circuit, wires can be twisted around each other in place of a capacitor, for very low pico farad capacitance:
https://www.youtube.com/watch?v=v1wWL6TGWOE
Once an oscillating LC circuit is established, other things can be done.
Bob

F6FLT

  • Sr. Member
  • ****
  • Posts: 394
Re: Simplest oscillators for DC
« Reply #50 on: January 28, 2019, 04:29:15 PM »