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Posts posted by Um...Me123

  1. OK!  I'll take your word for it even though I'm still not sure what you mean by mains and secondary.  It said the neon works fine with 120V by the way.

    Looking back at the schematic is it ok if I run the other DC things off the approx. 24VDC the transformer and bridge put out?  What I mean is, can I run seperate wires comming off this circut between the 2200u cap and the 100n cap?  I thought I read somewhere that the 2200u was called a smothing cap in this case so I would think to put the wires after (to the right of) that.  Is that right or just branch off right after the bridge?


  2. [glow=blue,1,900]I think we should just re-name this Um...Me123's questions thread ::)

    Ok I have dilema.

    My circuit consists of:
    2AA supply (3V)
    two 3.2+V 30mA white LEDs--wired in parallel
    two 1.7V 20mA red LEDs---wired in series

    With being wired the way they are there is no need for a resistor right?
    My problem: If I touch the wires for the whites they work fine.

  3. Hey guys got a couple things for the supply(and general use) from radio shack the other day and the online parts should be here any time now.
    I have a quick question about something not related to power supply but I didn't want to create a whole new thread.
    I had a RC car from my child hood years (which in my case isn't very long ago) that I took appart.  The remote used 2 forward backward switches for each real wheel.  (the kind where you push one forward and one back and it gives you 360 spin)  It had 1 motor for each tire and just reversed the polarity to go backwards.  Looking at the remote the buttons for each tire are essentially a SPDT (its a thin strip of metal in a "N" shape where the center is neg and the two outsides are bent down to make a connection).
    Because the output to these motors is a decent sized voltage/amperage I was thing of making some type of wireless switches out of it.  I want to be able to control 4 relays individually with 4 SPSTs instead of the 2 SPDTs that reversed the polarity.  How do I turn the reversing polarity into 2 seperate circuits.
    Sorry if I did a bad job explaining it.

  4. Well I was hoping for at least 1A (for the project in general) but with the wall trans. will I not be able to even get the full 1A out?
    Would the best idea would be to just scratch that idea and go back to the 25V 2A CT? (<thats what you call them?)

    The box I'm making this in is 8"x6"x3" so when you (and by you I am now talking to audioguru) were talking about the LM317T getting too hot and shutting down (that was what you were were saying right?), a 60mm fan should easily keep it cool with that (I guess you said it was small) heatsink?

    Check out my other questions in the previous message...Staigen...thanks alot for all your help on this!  I think Staigen deserves a promotion!  He only has 3 stars!  Maybe he has only made 105 post or something like that but he can be an exception.

  5. About that LCD...sorry for being persistant ::) Why would it jump around?  What is it made for if it jumps all over on a DC?  One person who rated it said he use it on a battery and it just jumped in the tenths (in other words what is the difference between the supply and a battery as long as your not turning the pot all over).
    Also I will have no problem powering it.  I (already) have some lighted toggle switches that I want to use..I'm including outlets on each side of the box that can be turned on and off for things like glue/solder gun so there is no unplug--re-plug.  So I can light the switches and the meter with a 9V battery and turn the whole system on and off with a DPST (<no problem with the meter saying on Staigen :))

    Also check out my question about the capacitors in the previous message.  That's where I'm still confused.

    I should've know with that meter...the volts will be even between the meter and the outputs no matter what...I was thinking with the rules of amps for some reason.  By the way:  Do I actually need a shunt (if so what kind)?

    Do you always have to have a capacitor to use a 555?  (I know, A very off subject question but I have some 555s and a breadboard now but I dont have capacitors handy.  Do you suggest I get one of those packs of 50 (for example) different capacitors and one for resistors to be able to expiriment with different values for projects?

    I was thinking...(as I usually do alot of)..Those chassis mount trans. Do AC to AC the u have to have the bridge and the cap.  I can't think of when I'll need anything above 12V so wouldn't it just be easier to ad a 13.5V 1A AC to DC wall trans. and can skip some of the problems.  (^The 24V ones don't go up to 1A^)
    >>If I can do this, what all do I eliminate/change?
    Would the LCD not flicker then? ;D
  6. I'm sorry that I can't put all my questions together and not keep posting all the time AND I'm sorry that I'm too dumb to be able to figure this out for my self.
    enough apologies
    I read somewhere in the discussion board something about the voltage of the bridge-it was something low like 30V (maybe it was amp?)
    My question is can I use one that says 600V!?

  7. AC usally stands for Alternating Current, and AC is input to the rectifier bridge, or, if it dont have a bridge, to the rectifier

    Aren't we using an AC to DC transformer here?
    This power supply isn't for AC current is it? (the output that is)
    Well I think I get that part...second question:
    I'm still learning about the properties of electricity but I was looking at www.allelectronics.com and they dont have a 28V trans.
  8. I was lookiing at that second bench supply (the .pdf one) and I it looks pretty complicated (for me) but I think I can do it if I really try.  I just notice one quick thing (and I would have WAY more questions but I can go to my brother for those)...What's a DPCO (toggle) switch??..I know all the others SPST, SPDT, DPST, and DPDT.  Thanks for your help everyone!!
    Any ideas on something really easy to help me understand how the 555 works?  Make a LED blink or something.

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