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  1. K

    low frequency timer

    You will never improve the stability of RC clocks much. Smaller caps mean larger resistors that are more subject to temperature...time and temperature drift always win. :( Use your 32.768KHZ (standard) crystal with a CD4060 (last output) to get a 2Hz signal. Follow this with four CD4017's in...
  2. K

    low frequency timer

    You didn't specify, but if you can be line operated, here is an accurate 1 second clock signal: http://www.play-hookey.com/digital/experiments/one_sec_line_clock.html If you're expecting battery operation you might try this for an accurate 1 second source...
  3. K

    Simple Circuit

    That's better. Essentially you're looking for a tachometer circuit: "separations" per minute instead of "revolutions" per minute. One of the issues is how frequently the contacts will "officially separate". This is an matter of "contact bounce". Very short, rapid separations as the contacts come...
  4. K

    On/Off Delay Timer

    You might want to look at :http://www.zen22142.zen.co.uk/Circuits/Timing/24hour.htm Perhaps two could be linked to give you hours on and hours off. Ken
  5. K

    Simple Circuit

    Can you explain what you're really trying to do? What would break a circuit? It may be easier for us to help solve your problem...than try to solve your solution. ;) Ken
  6. K

    How many 12 volt Batteries would I have to hook up to run a clothes dryer and two sum

    You would need many huge batteries and a very big inverter to convert the DC to AC, needed by most appliances. "I am trying to cut back on electricity usage" Where do you plan on getting the energy to charge the batteries? Charge them off the power line? The line/charger/battery/inverter...
  7. K

    Capacitor Glue

    There are many different formulations of "RTV". Some are compatible with electronics (non-corrosive), some are not. What manufacturer/product are you using. ken
  8. K

    Hamlin 721A-0100 Relay

    Good luck. By the way, what are you doing? Ken
  9. K

    Capacitor Glue

    I don't know. In the past I've always used silicon RTV made to be compatible with electronics. The acrylic might work OK. You might email the manufacturer and ask them. Ken
  10. K

    Hamlin 721A-0100 Relay

    Have you checked with Hamlin? I don't see that exact number, but they do list the 721-A-XX-XX series: http://www.hamlin.com/specsheets/HE700.pdf Are you sure you have the part number right? Ken
  11. K

    10MHz clock generator

    Interesting! Most of the ones I'm familiar with have a TTL compatible outputs, with a few nS rise times such as this: http://www.ctscorp.com/components/Datasheets/008-0258-0_E.pdf Ken
  12. K

    Motor speed control

    I think you will need a large, geared, brushed, DC motor with a PWM (pulse width modulation) driver and tachometer feedback to a microprocessor controller to achieve your specifications. Ken
  13. K

    Capacitor Glue

    Be aware that not all silicone sealants are compatible with electronics. If I remember correctly, the ones with a strong acetic acid smell are a no-no, because it will cause corrosion. ken
  14. K

    electronics softwares...

    I can't vouch for Windows 7 compatibility, but I found ExperssPCB's schematic program very intuitive. It's free, so download it and try: http://www.expresspcb.com/ Ken
  15. K

    Touch Lamps

    For building one from scratch, Google: touch switch circuit For less challenging options, Google: touch switch circuit kit Ken
  16. K

    10MHz clock generator

    Google: 10Mhz clock oscillator You will find lots of vendors of metal, 4 pin DIP packages. Ken
  17. K

    typing equations...

    MS Word 3 has math symbols, so I assume Word 7 has them too. Insert > Objects > Create New > Microsoft Equation 3.0 > this beings a math editor tool. Ken
  18. K

    electronic technician

    jeff, First "electronic 'engineering' degree", almost everywhere, is considered a 4-year degree. This said, is so you don't confuse potential employers. Repair of consumer electronics is pretty much a dying field. Depending on what you find fastening in electronics, industrial electronics...
  19. K

    hiccup mode power supply

    Google: hiccup mode power supply You should fine all you need. Ken
  20. K

    Circuitry for a Trivia Quiz Night

    Zepher, With the SCR circuit, be sure you use "non-sensitive gate" SCRs. "Sensative gate" SCRs will not work properly. Been there, done that. Ken
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