Search results

Search Forums New Posts
  1. C

    Advice for Solar Charging Circuit

    I have a circuit to charge the battery from 0.5v but it will take over 2 weeks to charge the battery.
  2. C

    I can't see how this will work

    Try this transistor Schmitt Trigger
  3. C

    Pilot light to detect break in resistive load

    Use a diode to detect when the temperature is low A diode will allow you to detect the temperature at a remote location and drive a LED or relay or buzzer
  4. C

    Help with detecting open switch

    LEDs work on 1mA. Use a super bright LED
  5. C

    I can't see how this will work

    You really need a schmitt trigger
  6. C

    Pilot light to detect break in resistive load

    Can you put a diode near the element to detect the temperature? Can you afford to lose 0.7v across a resistor?
  7. C

    Help with a transistor inverter circuit

    Here is the circuit:
  8. C

    Different power supply or just throw in a voltage regulator?

    The lighter battery will not work. The best is an alkaline 9v battery. It will blow up your resistor. Use 3 x AAA cells as this is the correct voltage for the front end.
  9. C

    Ohms to trigger a switch

    You said the voltage is 5v when empty, so there is a safety resistor in the circuit.
  10. C

    Ohms to trigger a switch

    Here is a simple transistor circuit
  11. C

    Need opinions on regulation.

    Buy a SMPS from eBay for $1.10 2AMP 96% efficient. with FREE shipping. You are wasting your time with 7805's http://www.ebay.com/itm/DC-DC-LM2596-Step-Down-Adjustable-Converter-Power-Supply-Module-1-3V-35V-F5-/291362318499?pt=LH_DefaultDomain_2&hash=item43d68c28a3
  12. C

    Calculating resistance and Base current

    Your teacher doesn't know what he is talking about. Vout can never reach 3.2v. He has made a BIG mistake and I can see how he has made it.
  13. C

    Voltage range

    How much current will the signal supply? How accurate do you need the output to be?
  14. C

    Need opinions on regulation.

    Use 78L05 and put 1k on the output. You will need to heatsink the 78L05
  15. C

    Some pcb questions

    I have used Elecrow 40 times in the past 9 months. Their boards are absolutely perfect. Not a single mistake. They charge $25.00 for 10 to 12 panels 100mm x 100mm, double sided HASL, silk screen . Always keep your boards to a modular size of 100mm x 100mm and cut them yourself if you have 5...
  16. C

    Making a PCB that can have connections changed

    You put a set of 20 rectangular pads on the board connected to 20 pads with a 10 thou track. These pads will be tinned and the track can be cut and enameled wire can be used to join any pad to any pad. Never use vias as you may lose your "track."
  17. C

    Test bench power supply

    How many times in 20 years will you need a DUAL supply?
  18. C

    555 timer Stays ON after trigger

    You have the 100k and 10k in the wrong positions The 33u needs to be connected to 0v so pin 7 can be used. You will have at least 4 "blocks" and a 74c14 will be best
  19. C

    Need to find a way to do different functions basedon incoming voltage

    What an absurd solution to use a 24v relay. Where were you when they invented the TRANSISTOR ?????
  20. C

    Need to find a way to do different functions basedon incoming voltage

    "How does the circuit turn off the red LED when 24 V is present? The microcontroller does that, along with the comparator.
Top