Recent content by CRE

  1. CRE

    Another PSU question.

    Hello everyone, I've been thinking for a while that I'd like to clean up my computer's power wiring... I know the usual methods of using loom, etc, and tying them out of the way, but what I'd like to do is make a box for each 3rd of my server case with one power in connector and 3 - 4 power out...
  2. CRE

    Piggy-backed PC power supplies?

    Well, after talking to my friend who asked about doing this, he's taken some time to think about it and decided to do the sensible thing..... buy a case big enough to fit a full ATX PSU.... Still, one of these days I might be inclined to experiment on this with a couple cheapie's.... just to...
  3. CRE

    Puggy Potty Alarm

    :-\ whoa..... umm, yeah what that other guy said.  :o Err, ok, well backing up a few posts, I'm sure the two 9v's in serial didn't fry the cap as I hadn't even used them when that prob occured. It may have fried one of the IC's granted, but as I said, I tested the voltages and they were...
  4. CRE

    Puggy Potty Alarm

    Well, I had it running fine on my breadboard.... I think I burned one of the ICs..... seres me right for not keeping enough IC Sockets on hand. I was wondering, if I use a larger bypass cap will it reduce battery life?
  5. CRE

    Puggy Potty Alarm

    Good to know, AudioGuru, so would one of the other opamps I listed as having on hand work better than a 741? The 741 seems to run fine... but I haven't tried a different one... all my others are dual or quad.
  6. CRE

    Puggy Potty Alarm

    Ok, so far, so good (excellent actually  ;D).... Now, how about an auto reset on the trigger? I imagine I could accomplish it myself using an opamp/comparator, but can it be done using fewer parts such as a transistor in combination with another cap and pullup resistor? Something which'll...
  7. CRE

    Puggy Potty Alarm

    It was definitely shorted.... because the 555 was still getting the trigger pulses. That's pretty muvh how I thought it was working, but
  8. CRE

    Puggy Potty Alarm

    Horay! Well, I swapped the ceramic cap I had in there (I wasn't positive of the value) and put in a 10nf Met. Poly. with the second pull up resistor and it works like a charm! I understand the basics of most parts of this circuit, but the cap and pullups escape me... I kinda see some of the...
  9. CRE

    Puggy Potty Alarm

    Hmmm...... not sure what I've done wrong, but if I keep the trigger grounded the circuit doesn't stop until the trigger is pulled from ground. I understand somewhat what you're saying about the op-amp, but as i said, right now 741's, 324's, 348's, and 1458's are all I have to work with.... the...
  10. CRE

    Puggy Potty Alarm

    Hey, wow, talk about a quick response... As a matter of fact I am using a 741.... didn't have any other type of single op-amp on hand. So as for volume, I'm either being limited by the piezo element or the single 9v supply... right? I mean, it's loud right now as long as the freq. is...
  11. CRE

    Spellcheck Error

    I keep getting this error whenever I try to use the spellcheck.
  12. CRE

    Puggy Potty Alarm

    Okay, I've built the circuit and it works well, I'll need to modify the trigger a bit, either a one-shot circuit or a long delay before resetting as the contacts may take a while to dry and stop conducting (if I'm not home). Also, am I correct in thinking that the gain is set by the 10K...
  13. CRE

    Puggy Potty Alarm

    LOL...  ;D Oh I've been there a few times.... then again I'm still a newbie.... but even I know that once I've "Mastered" something I'll always find more to learn. Thanks for going to the trouble Alun, I'll probably have time to breadboard this tonight. I'll post my results... well, I'll post...
  14. CRE

    Puggy Potty Alarm

    Hey guys, thanks for all the responses. For the time being I've set up a small analog buzzer from RatShack which made for some VERY amusing moments last night.... so funny, so sad.... poor startled little doggy..... so funny!I think I'll give Alun's circuit a shot, but I was wondering if I...
  15. CRE

    plzz give some raw idea about this project

    I presume, this is for some sort of medicinal use? In which case the frequency probably needs to be quite accurate... do you know the frequency needed? As for the circuit, if the use of this appliance is going to be tethered to the computer via the wiring anyway, why not box the driver and just...
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