Search results

Search Forums New Posts
  1. hevans1944

    Fast Switching Relay for High frequency Signals

    As per usual, the OP doesn't tell us what they are trying to DO, instead they inform us of their "solution" and ask where it can be procured. Lossless "high frequency" relay, huh? Where did the OP get the idea that such a relay even existed? I am pretty sure they don't make any in Pakistan, or...
  2. hevans1944

    Help identifying component

    From your photo it appears the buss bar strip is made from aluminum, which makes sense if the "tabs" were originally straight and die-cut from a flat metal strip before bending and looping over for insertion into the terminal barrier strip. Aluminum is of course almost impossible to solder. A...
  3. hevans1944

    LED Help needed

    There is a section called Project Logs that you can visit to see if posting there would appropriate to your needs. Or you can just start a thread with a descriptive title and post a description of what you are trying to do. The better the description, the better the answers you will receive...
  4. hevans1944

    Marconi TF 2370 spectrum analyser

    Try this link to obtain a free download of a zip file containing a pretty good user manual and schematics as PDF files. The zip file is about six megabytes.
  5. hevans1944

    LED Help needed

    Each string would consist of ONE LED and ONE series current-limiting resistor. This is all covered quite well in the resource that @davenn cited. Please READI IT!
  6. hevans1944

    UM66 is not giving full tone

    Experimentation is good. But it should be backed up with knowledge (theory), precise measurements, and good records of what was done... so the same experiments are not repeated while hoping for (expecting) different results... to do that is one definition of insanity. Just adding components...
  7. hevans1944

    UM66 is not giving full tone

    More like deliberately arrogant. His non-functional box is safely placed in a "drawing room," impervious to outside influences, and connected to a mains-capable switch "on the main gate outside." The do-dad musical melody generator appears to be like a gimmick from inside a cheesy greeting card...
  8. hevans1944

    Resistor to limit current to circuit

    Capacity of the power supply has nothing at all to do with the amount of current that is delivered by the power supply. This concept is so basic to the understanding of electricity that you should limit yourself to "playing" only with a handful of low-voltage cells (AA or otherwise) until you...
  9. hevans1944

    UM66 is not giving full tone

    Putting mains voltage on a doorbell push-button switch is insane. Doorbells are wired with low voltage AC, typically 12 to 24 VAC. The cheap push-button switches used for doorbells are not rated to switch mains voltage, which IIRC is 230 VAC, 50 Hz, in India. Not showing the complete schematic...
  10. hevans1944

    Heat shrink as water insulator

    Make sure you are using the right heat-shrink tubing. For a waterproof seal you need to use tubing that has an adhesive coating inside that melts when the tubing shrinks. Find some here.
  11. hevans1944

    Simple Metal Detector Circuit Keeps Beeping - Help

    @73's de Edd: Bit of nice detective work there! Unfortunately, the only feedback we have received from the OP, @itpelecnewbie, has been the rather terse and uninformative comment: The picture is posted. Some of these newbie posters are incomprehensible in their attitudes. For someone who is...
  12. hevans1944

    Understanding basic passive components: resistors, capacitors, inductors.

    @GeekGuy, that's an interesting blog you have there. Thanks for the tips on selecting resistors.
  13. hevans1944

    Simple Metal Detector Circuit Keeps Beeping - Help

    In this case, a picture is NOT worth a thousand words. Your picture is almost worthless in understanding what your daughter has cobbled together. What @(*steve*) requested was that you post a schematic diagram, NOT a picture of a jumble of wires and barely visible, value unspecified, components...
  14. hevans1944

    Electric ICE Exhaust Cut-out... why? and how?

    @Audioguru that's what happens when I jump to a conclusion based on a single example. I just assumed that, because the rental car company ordered vehicles with automatic turn-on of the headlights, that all cars sold in Canada had that feature. My bad. Thanks for the correction. Agreed. So it's...
  15. hevans1944

    Electric ICE Exhaust Cut-out... why? and how?

    IIRC, in Canada all cars have headlights that are automatically turned on when the car is started. I seem to recall this happening when I rented a car in British Columbia's Vancouver during a business trip one year in the previous century. Too bad there was no follow-up here in America. It's a...
  16. hevans1944

    Electric ICE Exhaust Cut-out... why? and how?

    Well, we may not be able to do that, but moderators can, and should, act as judge, jury, and (if necessary) executioner to maintain the decorum and "flavor" of this forum. Sure, there will be some knee-jerk reactions from time to time... some issues are so clear-cut that a knee-jerk response is...
  17. hevans1944

    Electric ICE Exhaust Cut-out... why? and how?

    Installing head lights with focused beams, pointed at oncoming drivers, is dangerous and possibly illegal. The light could cause me to veer right, start to go off the side of road, over-correct and ram head-on into the discourteous driver, or wind up upside down in the median or tangled up in...
  18. hevans1944

    Electric ICE Exhaust Cut-out... why? and how?

    Wow! I didn't want to start a controversy here about when, where, and why moderators should or should not close certain threads. I think the mods do a decent job keeping EP civil, safe, and purposeful as a place to discuss electronics. If someone, sometimes, thinks the moderators are bit too...
  19. hevans1944

    Electric ICE Exhaust Cut-out... why? and how?

    A recent thread (now closed) brought back memories of the 1960s and the Beach Boys song Little Deuce Coupe. Part of the lyrics say "she purrs like a kitten 'til the lake pipes roar ... you don't know what I got." I dug the Beach Boys songs at the time but had no idea what lake pipes were. I also...
  20. hevans1944

    +DC_out_rtn, what does this mean..

    Maybe this graphic from your linked datasheet will help:
Top