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  1. hevans1944

    Hand on the loading coil

    Please post a schematic of your receiver and its specifications. What range of frequencies is it supposed to tune to? What type of signal modulation is it supposed to respond to? Do you have any idea what you are trying to do? Why is your hand a part of the circuit you are tuning? All...
  2. hevans1944

    Sequencing output based on Power Cycling

    Rotary stepping switches, which used to be used in telephone exchanges to accept dialed-in numbers and connect the incoming line to the dialed line, are an obvious solution. Problem is finding and using them. @Harald Kapp's suggested steam punk solution would probably be easier to build today...
  3. hevans1944

    Led blinking instead of staying solid

    Thanks, Bob! I realized my mistake (and edited the post to correct it) after seeing another post from November 2018 that had a reply from @73's de Edd that had a nifty LED chart attached. So, I grabbed a copy and added it to my post. I often use 330 ohm resistors with LEDs and 5 V circuits. I...
  4. hevans1944

    Led blinking instead of staying solid

    LEDs are dirt cheap. Spend a buck and buy a dozen or so to play with. Throw away the mystery blinking red and green LEDs, or maybe save them to make decorative lights someday after you have mastered the mysteries of Arduino. Small red LEDs need about 20 mA of current and drop about 1.8 V when...
  5. hevans1944

    Spaghetti Engineering pcb

    You either need very deep pockets full of cash or you need to be a member of a three-letter agency with a black budget to afford to reverse engineer something as old and as complicated (multiple layers with blind thru-holes and surface mounted devices) as the PCB you described. Most if not all...
  6. hevans1944

    Accelerometers for accurately indicating position?

    For a milling machine, you need something that is accurate and repeatable. Linear (optical or magnetic) tape "scales" interfaced with electronic up-down counters come in many varieties and are recommended for the precision you need. Ask the vendor of your mill if they offer a retrofit readout...
  7. hevans1944

    CHARGING OF EVIL FUTABA BATTERY PACK

    I have used both brands, but the Panasonic Eneloop cells seem to charge quicker and last longer, at least for my applications. It was the Energizer cells that prompted me to purchase the Energizer 4-cell charger, to charge about eight of them, a few years ago, mainly for flashlight and digital...
  8. hevans1944

    IR IMAGING DEVICE on the cheap

    I suspect it is. Why do you think a thermal imaging camera would be of any use at all for marine casualty searches? Are you looking for living survivors above or below the water? If not living, then after a few hours exposure to the marine environment everything reaches the same temperature. A...
  9. hevans1944

    Use for old scanner?

    When they went to "trunked and encrypted communication" did they also change their radio operating frequencies? Perhaps if you have any friends in the NSA (No Such Agency) they can tell you how to add decryption hardware and software to your scanner? Can't be too complicated, if it is supposed...
  10. hevans1944

    CHARGING OF EVIL FUTABA BATTERY PACK

    Ni-Cad batteries, huh? Aren't those the ones that "remember" how much you discharged them, and then stubbornly refuse to accept a full charge again? And, IIRC, don't they also grow internal "whiskers" that short individual cells, playing havoc with attempts to charge series-connected cells in...
  11. hevans1944

    Can Anyone Identify This Component?

    "If it has a Triac and a 2 legged active part, it must be a DIAC" @Sunnysky: go back and read the original post.
  12. hevans1944

    IR IMAGING DEVICE on the cheap

    Very much out of line. Suggest you read up on thermal infrared cameras, which are mainly sensitive to IR radiation in the 8 to 14 μm wavelength range. Silicon-based visible imaging cameras only have a near-IR response that peaks at about 0.9 μm. FLIR Corporation makes a suitable imaging camera...
  13. hevans1944

    isolating transformer and variac - what order?

    I have never considered the "cradle to grave" cost of lamps whether LED, curly-bulb, incandescent, halogen incandescent, neon, or whatever. Years ago electroluminescent strips were popular "night lights" that apparently lasted forever and consumed very little energy. You can still buy them, but...
  14. hevans1944

    isolating transformer and variac - what order?

    Youse guys livin' in England, Europe, Asia, Australia... anywhere except here in the United States of America... have the ability to buy something that is now forbidden to us: 100 watt incandescent light bulbs. Even smaller wattage incandescent lamps are slowly being pushed off our shelves in...
  15. hevans1944

    Can anyone help me in using UART

    Geeze. @mrshell: Welcome to ElectronicsPoint. This is not a forum where we do all the work. I recommend that you try this link to a STONE User Development Guide before doing anything else. And the next time you do a drive-by and post something here, please provide ALL the information relevant to...
  16. hevans1944

    Hard to find replacement part.

    Sometime in the last century I thought I needed a single-lens reflex (SLR) camera with a macro lens and fancy lighting to take good pictures of electronics. This did work well, especially with my Canon Rebel 35mm camera mounted on a tripod with a remote shutter release cable attached to the...
  17. hevans1944

    Momentary Switch to directional DC motor

    Duty cycle limitations are NOT addressed with the current toggle switch. It is a real possibility that an uninformed handicapped person could exceed the ON-time limitation, or not wait long enough for the OFF-time cool-down to occur and therefore exceed the duty-cycle limitations. Depending on...
  18. hevans1944

    Where to add dimmer in ac led bulb?

    Your "experiment" is a colossal FAIL. Lessee... you want a dimmable, bright, LED light (presumably white) with 75 - 100 watts power input capability. Plenty of those available. Choose a reliable manufacturer (Cree would be my first choice) or take a chance on an Asian import, your choice. Cheap...
  19. hevans1944

    Momentary Switch to directional DC motor

    This appears to be a similar problem to one discussed here in an earlier ElectronicsPoint thread. A small dedicated microprocessor would be able to sort your requirements and implement a single push-button switch solution. There are many push-button switches available for use by the...
  20. hevans1944

    Bistable Multivibrator

    Not your fault that @Albe uploaded an image with poor resolution. The Amazon website has much better (and more) images. See my post #12. One of them clearly shows the IC to be an STC 15F104E, a microprocessor with 4K (bytes?) of program memory. Switch bounce (and induced noise pick-up) is easily...
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