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  1. gorgon

    Need help identifying a connector

    There looks to be something written on the edge wher the leads go in. Is it more than the 's' I'm seeing? TOK ;)
  2. gorgon

    Mysterious disintegrating 317s

    If your diagram is correct, the one thing you do not protect against is a positive peak voltage from the motor into the output of the regulator. How about trying with a serial diode from the output capacitor to the motor/diode and add a separate capacitor or a capacitor/resistor over the motor...
  3. gorgon

    People 'trading' their hardware hacks?

    At least in my country that would be a bargain for a custom made PCB, let alone a blinking LED added. :D But, since I live in Europe you can't sell any electronic consumer product without a CE certificate, including ROHS. I suppose it is easier overseas. TOK ;)
  4. gorgon

    Frequency Analyzers measurements

    @Davenn I really admire you, the giant mountain of patience :) TOK ;)
  5. gorgon

    Circuit Board clean up question.

    I used a sharpened match to poke out the solder when melting it from one side. It doesn't suck a lot of heat from the solder and push it aside. It is a last resort, but it works. This is why you should remember to use thermals when you do PCBs with large filled areas of copper or planes...
  6. gorgon

    regulating amperage

    The only way to reduce the current is to reduce the voltage. If the motor is rated for 12V, you'll also reduce the motors power range when reducing the voltage. You'll need to get a rated driver for the rated current. TOK ;)
  7. gorgon

    regulating amperage

    Note that one ULN2003 chip can only handle 500mA in total. So it doesn't matter how many of the separate drivers you parallel, you will not get more than 500mA safely from one chip. You need to find the needed current for the motor and use a driver big enough for that, or reduce the voltage...
  8. gorgon

    Sanyo IC's

    If you search here http://www.alldatasheet.com/ for 'STK3062' and 'STK-3062' you'll get the 2 variants. The one with a '-' is the old one. They look more or less equal, the only difference is a couple of capacitors drawn in the old one, maybe parasitic. TOK ;)
  9. gorgon

    DC power supply

    You should really take care and use a diode on alle the outputs, to separate them. To compensate for the diode loss use the same type of diode in the ground lead, to increase the voltages accordingly, In fact a single diode connected to all the regulators should be ok. Not all types of...
  10. gorgon

    Charging one battery stack from another

    As long as you are using lead/acid batteries, you can't use higher voltage on one of the batteries, even if you have a drop in the cable. The mechanics around this is that the only difference you'll have between the two batteries, is the fact the the one with a small drop will top up slower...
  11. gorgon

    88V to earth from secondary of 12V 10A power supply....

    If this is a switchmode supply, it could be that you may have a static voltage buildup between the primary earth, and the floating 12V. I've seen similar buildups of 150V on isolated laptop switching powers, making RS232 ports migrating to hell. :D The real question is then, is there any...
  12. gorgon

    Reverse the voltage?

    It depends on the type of signal, and the IC it's coming from, but the term is to invert the signal, at least if it is a logic signal. If it is analogue in nature, use an opamp as said. TOK ;)
  13. gorgon

    Positive Ground

    Most grounds are referenced to 0V, so when you say positive ground, the meaning is really that you have a negative supply voltage. Since a positive supply voltage is the norm, there are som issues connecting things together if you have both systems. If you have a single power supply, you...
  14. gorgon

    12V / 6A Power supply. Help with Buck and Boost converters + OR'ing circuit

    I've used the Webench here http://www.ti.com/ww/en/simple_switcher_dc_dc_converters/index.html One chip that came up is LM3481. I've never done a SEPIC design here, but several other designs. I tried to use your parameters for a design, tuned to max efficiency, and got a complete design...
  15. gorgon

    Noob questions

    The reason is simply that the voltage over the 1k resistor equals the voltage drop over the LED. With a 3k resistance the voltage over the 1k resistor is about 2V(6/3), or 1.93V in your case. This is in the ballpark for a coloured LED, like a red one, for a low current like 2mA. In addition...
  16. gorgon

    12V / 6A Power supply. Help with Buck and Boost converters + OR'ing circuit

    You should look for a SEPIC switcher in the case where you need to have both a buck and a boost regulation. TOK ;)
  17. gorgon

    Replacing thermal fuse with something that will reset

    Yes, that should be the function. It opens at 45 degC and close again at 25 degC. The problem may be to place it correct in the machine. You need to place it at the same location as the fuse, and with a good thermal connection. You should be aware that when the thermostat is closing, the...
  18. gorgon

    RS-232/TTL encoder

    Normally you use an output to an input, but this is maybe just a way of talking. You should check out the driver chip to see if all voltages are present. Depending on how old the boards are there may be several voltages coming in, or they are made on the board. The driver chip will need a...
  19. gorgon

    High density boards with gold plating for inner layers

    I've never heard about gold on inner layers before. On the outer layers it's common and necessaery when using BGA chips. I don't know what you normally plate with on the inner layers, if anything other than copper, but the only reason to plate with gold could be a wish to reduce the build of...
  20. gorgon

    Crashing after 145 seconds

    I mostly rely on your statement in the first quote, and are interpolating from there. And no, I've not used the modern BASIC compilers. From tests I have read though, I've had the impression that even compiled BASIC has a speed loss, compared to other languages. This again imply a background...
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