| Author |
Message
|
| abudantia |
 Posted: Wed Oct 31, 2007 5:25 pm Post subject: Need help with Pulse DC |
 |
|
Forum Freshman
Joined: 12 Oct 2007
Posts: 8
|
Here is what I have.
A pulsed DC signal that when displayed on my voltmeter it reads more than 1200 V and 200 ma @RMS. I measured it with ACV and DCV and it still read 1200. It pulses at least 80 times a second; but for some reason It doesn't have enough power to turn on a little flashlight bulb or a simple AA motor (both DC).
Any ideas on why it isn't powering anything?
Could the volt meter be giving off false readings?
Thanks, |
|
| Back to top |
|
 |
| 425 Chaotic Requisition |
| Posted: Wed Oct 31, 2007 5:31 pm Post subject: |
|
|
The Doctor
Joined: 18 Jun 2007
Posts: 2684
Location: UKGBNI, England, Derbyshire
|
I wish I could help. Maybe the meters are draining the power? Placing the meters after the bulb-would that work?
_________________
"There is no knowledge, that is not power" - Ralph Waldo Emerson. |
|
| Back to top |
|
|
| Harold14370 |
| Posted: Wed Oct 31, 2007 5:34 pm Post subject: |
|
|
Forum Professor
Joined: 13 Apr 2007
Posts: 1244
Location: Pennsylvania
|
| Yes, I believe it's quite possible your meter is giving a false reading. If the light doesn't light, and it is rated for that voltage, that would be proof positive. The cheaper meters I think just read the peak voltage and give you a "rms" voltage that is .707 of the peak a-c. There is such a thing as a meter that reads "true rms." |
|
| Back to top |
|
|
| abudantia |
| Posted: Wed Oct 31, 2007 6:29 pm Post subject: |
|
|
Forum Freshman
Joined: 12 Oct 2007
Posts: 8
|
It gave me a peak of over 1600v and 350ma so I thought I would round down. My meter is a cheap-o and it reads a AA battery as it should be and it reads the 110v coming from the wall. I will try a analog one, thanks.
Another question for you how do I create an frequency of over 1mhz (1,000,000 cycles per second)? I think that a welder operates around 1.2mhz but I am not sure.
Any advise?
Thanks, |
|
| Back to top |
|
|
| Harold14370 |
| Posted: Thu Nov 01, 2007 9:12 am Post subject: |
|
|
Forum Professor
Joined: 13 Apr 2007
Posts: 1244
Location: Pennsylvania
|
|
| Back to top |
|
|
| abudantia |
| Posted: Tue Nov 20, 2007 1:53 am Post subject: Need a little more help, Still a little lost |
|
|
Forum Freshman
Joined: 12 Oct 2007
Posts: 8
|
I need to create a electrical frequency between 1.5mhz and 2.6mhz. I would like it to operate with less than .01a and 250v. I understand how a LC circuit works and know how to read a basic schematic but am no sure about the simple things. I assume I need a circuit board, but what size inductor and capacitor do I need, what do i use to connect it to my solenoid, what would I use for the input? I want to keep things simple. I am not trying to be lazy but am just a little lost when it comes to the specifics.
Thanks for all the help,
Abudantia |
|
| Back to top |
|
|
| Twilight |
| Posted: Mon Nov 26, 2007 7:31 am Post subject: Post subject: Need help with Pulse DC |
|
|
Forum Freshman
Joined: 25 Nov 2007
Posts: 19
|
Hi abudantia
First of its possible to have 1200V rms and 200 mA rms with 0 watts of real power. If your voltge and current spike occur out of sync then you will have no real power, it could almost be said that you have a very power power factor since all your power is imaginary.
Now im not sure i understand you right, you want to generate a signal, osscilating between 1.5 and 2.6 MHZ. As far as i know you cant generate a signal with a LC circuit, these circuits can be used as filters becouse they have a natural frequency at which they like to osscilate and reject the rest. However they cant create their own signals.
To create a signal you need something like a Wien bridge.
http://www.interq.or.jp/japan/se-inoue/e_ckt18_2.htm
But you dont want to make a sine wave right ? you want a series of pulses. Maybe you can attach a comparator to the output of the wien bridge to switch between two voltages values at a predefined value(i.e switch voltage between 5V and 0V when sine wave greater than 2.5V or so), not sure im gonna have to think about it a while. |
|
| Back to top |
|
|
|
|
