Search results

Search Forums New Posts
  1. (*steve*)

    Digital circuit question help.

    Ok, the questions I asked require a basic understanding of what an A-D converter does, and all the other required information is in the question. You need to go back and revise what you have been taught or perhaps do a little research. Is there any suggested reading that you may have skipped?
  2. (*steve*)

    Digital circuit question help.

    For the first question, can you tell me the range of input voltages and the expected output at these two voltages?
  3. (*steve*)

    Electronics Design Process

    Having a schematic is nowhere near step 2. and your steps 3 and 4 kinda don't ever happen. And whilst you might simulate the circuit, you may also build a prototype, or at least try out various components of your circuit. Here's what I'd say is _a_ process: Determine requirements Create a...
  4. (*steve*)

    Microcontroller project for my pool pumps

    Have you tried this with a smaller load (say a light bulb) to confirm it's not something related to the load? With dummy loads, see if you can close both contactors independently and that it's just the combination which causes problems. Can you show us how you've wired the contactors? What...
  5. (*steve*)

    playing around with a current sink.

    Why 130Hz, 1.3kHz, and 13kHz? The signal generator was set for 1300 and I didn't bother changing it :-)
  6. (*steve*)

    playing around with a current sink.

    Here's the circuit: My calculations indicate that the 10M resistor should not be able to supply sufficient base current to Q1, but it does. I will probably reduce the value of this resistor to allow for devices that have lower performance. Reducing the value of this resistor has the effect...
  7. (*steve*)

    playing around with a current sink.

    I'm building a circuit with an active load which happens to be a constant current sink. One desired factor is a high impedance, and since it's for an audio application I really want it to be flat over audio frequencies. The results first (please excuse the mobile phone images. At 130Hz...
  8. (*steve*)

    240V ac LED bulb failure

    Both, but sometimes bayonet are a little more expensive... Oh and the ones in my office are 2000 lumen (I checked). Neither appear to be on their web site. My wife has some tasks for me that will probably get me to Bunnings tomorrow so I'll report back on the actual items :-)
  9. (*steve*)

    240V ac LED bulb failure

    Or $5 from Bunnings with a pretty much no-questions asked 12 month return policy (keep your receipt). I've taken one apart after it "failed" and found out that the problem was a bit of melted glue. the newer versions are better designed and don't suffer the same problem. Aside from the glue...
  10. (*steve*)

    Wire for 12v in-ceiling services

    The rules are pretty simple. :-D
  11. (*steve*)

    Wire for 12v in-ceiling services

    Heh, technically you require a license to run cabling for your network.
  12. (*steve*)

    Transistors for higher voltages

    That's not strictly true. In theory a pair of mosfets can be placed in series to withstand a higher voltage. In some exotic applications I've seen people trying to use three or more. When turned on there is no problem. When turned off, there are a few problems, most of which can be worked...
  13. (*steve*)

    Transformers

    Are the voltages AC or DC? If AC the theoretical answer is yes but the practical answer is no.
  14. (*steve*)

    Transistors for higher voltages

    Best to get a single 80v (or better 100V) device.
  15. (*steve*)

    Hope I didn't make too big a mistake with my radio...

    This images are not in focus and don't show anything obviously interesting. Perhaps better photos with some explanation?
  16. (*steve*)

    Reading Datasheets

    Ok. The most important things are the absolute maximum ratings. Make sure you never exceed these. Then, knowing what the most important sources are for your application, ensure they are acceptable and read the fine print (graphs and tables) to make sure there are no gotchas. Often you will...
  17. (*steve*)

    Reading Datasheets

    Point is at the datasheet in question and tell us what you want to do with the chip.
  18. (*steve*)

    Design Spark PCB

    I generally start with rubberbands and move stuff around until it looks tidy and like it will route well before I lay down any tracks. Can you get the software to move it to a PCB layout but not do any of the routing?
  19. (*steve*)

    SMD code help

    Sorry, you have tried the same source I would have tried.
  20. (*steve*)

    RGB leds color changing help...

    That instructable is basically what I said. Controlling by a microcontroller is generally achieved by pwm with a pass element to increase the available current and some means to limit the "on" current. You need to buy simple RGB LEDs, not those with fancy interfaces.
Top