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  1. gorgon

    How do i use these thingys?

    Dorke is right. The simplest way t osee it is to look at the arrows in the transistor and the LED. They point from + to - for bipolar transistors.
  2. gorgon

    mini christmas lights

    You didn't say the wattage of the 3.5V bulbs, if it's much higher than the other bulbs you may have your answer.
  3. gorgon

    Low voltage disconect circuit

    You should add in some hystreresis in the circuit, or a latch OFF function, since the voltage will rise when the load disappear, and draws the relay, drop the relay, draws, and so on. One thing to keep in mind is the current draw of the relay, this will reduce the life of the battery. If you...
  4. gorgon

    PCB minimum thickness (rigid)

    I've made 4-layer FR4 PCBs 0.8mm thick, but I see that some manufacturers has a limit around 0.4mm. I don't know if that is the thinnest you can get to a normal price. I suppose you know that PCBs that thin is flimsy, and not very 'rigid'. I would never have made 'large' PCBs in that thickness...
  5. gorgon

    What is the diode going to?

    The R2 is the pullup resistor, since it is connected to the MCLR input. R3 and C1 forms a LP-filter to remove bounce glitches from the pushbutton, when activated. R3 will also protect the pushbutton from the high discharge current when shorting C1, this protect the contact points from 'welding'...
  6. gorgon

    What is the diode going to?

    The zener and R1 is used to stop the programming voltage to feed back into Vdd from the ICSP via R2. The pushbutton is normally used to reset the mcu, and needs a pullup to Vdd to function correctly.
  7. gorgon

    Help, connecting a 3-position/2-Pole Slide switch

    I found this, and it should be right. http://jf-switch.en.alibaba.com/product/538863293-210224272/8_pin_smd_mini_slide_switch_SS_23E04_2P3T_.html Now you only need to find a place to get a single switch and not 2k.
  8. gorgon

    Help, connecting a 3-position/2-Pole Slide switch

    Could it be that your original switch was a 2P3T, or a dual 3-way selector? 1 an 5 would then be the common, switching between the 3 other. The best is to check out the old switch to see how it is switching.
  9. gorgon

    Choosing right diode..?

    What type of diode you can use is depending on the current drawn by the relay. 1N4001 is a 1A max diode, 1N5400 is a 3A max, both 50V. If the problem is that one or more switches activate the same relay, you can use a diode for each relay, from each of those switches. As said, a diagram or...
  10. gorgon

    Rest in Peace, Kris

    Very sad news to hear. Rest in peace, Kris
  11. gorgon

    Assembling splitted integer C

    If you need to transfer data securely, I would use a CRC on the data, so you know when they are wrong, and can ask for a retransmission.
  12. gorgon

    PIC 1.5V Output

    Why not use a standard LDO regulator for a 1.5V supply, at least if you need some accuracy. You can get regulaors with several 100s mA outputs at SOT23 like sizes or less. Not much real estate on the PCB.
  13. gorgon

    RAM Chips

    OK, so you want to register a timestamp from a 1GHz clock, at a 1kHz'ish rate? I would think that you will need some ultra high speed logic to count and latch the time, at least part of it, and a microcontroller to read and transmit the time stamp. As long as the latency of the latch process is...
  14. gorgon

    scroll message on an LCD...

    It's generally faster to write a space at the beginning or end of the scrolling text, than clearing the whole display. That normally takes several ms, and there will be a blink in the display. When writing characters, and space, the change is smooth. Or as smooth as the programmer can manage to...
  15. gorgon

    Using 74HC4052 for UART

    The main problem is not to control the switch, but to know when to listen at what. It's a question of synchronization of both Tx and Rx, and it all comes down to the protocols used one each channel. You can't work at more than one of the two at the time, so you need close control of what is sent...
  16. gorgon

    What is your favourite type of component?

    To make something at all you need most of the choices, plus more, so I can't say anything is a favorite. You need what is necessary to make and hit the target construction requirements. On the microcontroller side I do have some favorite brands, but that is different question. I just recently...
  17. gorgon

    code repeat??

    What happens if porta.fo is NOT = o?
  18. gorgon

    230V led driver, which one has low failures?

    You should also take into account that 230VAC will have a peak value of 325V if you want to make a long life circuit. The DC circuit(2) is made to supply a chain of 30 LEDs, so you need to recalculate the capacitor if you want to drive only one LED. You should check the calculations anyway, to...
  19. gorgon

    Need some help with this temperature sensor

    I've seen 1-wire temperature sensors from Dallas like the DS18x20 in a cable assy like this, but to read it you need to use the 1-wire protocol.
  20. gorgon

    assembly Instructions

    Inside each microprocessor/ controller there is a hardcoded statemachine that process each instruction like it is coded. This statemachine is the reason that there is a difference in the number of clock cycles for the different instructions. Each programming instruction will run its own small...
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