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  1. KrisBlueNZ

    Troll refuses help, prefers to insult moderators (was Video Generators video test signals)

    Why do you think all the moderators here who have got to know you - and moderators at other forums too - are just control freaks and want to get rid of you just because we hate you? Do you think other users have similar problems with the moderators?
  2. KrisBlueNZ

    Troll refuses help, prefers to insult moderators (was Video Generators video test signals)

    Danny, try this. Think about how many times you have been banned from Electronics Point and from other electronics forum sites. WHY do you think that is? Is it because we all just decided to hate you? No, because we don't even know you, and we have no contact with the folks at other sites who...
  3. KrisBlueNZ

    MOSFETs that make you scratch your head..

    How is your ATtiny powered? The 0V rail of the ATtiny circuit needs to be connected to the MOSFET's source.
  4. KrisBlueNZ

    Detecting spike from DC relay

    So you are measuring the characteristics of relays by applying a ramp voltage to the coil and monitoring the NO contacts to see when the armature moves? And you want to detect the armature moving before the contact state changes? How about monitoring the coil current. I think the movement of...
  5. KrisBlueNZ

    FM modulator light only and no transmitting

    I'm not sure because the markings on the board disagree with the colours of the wires that are currently soldered to it. Plug it into your car and measure the polarity of the voltage between the red and black wires. If red is positive and black is negative, then connect your red and black wires...
  6. KrisBlueNZ

    Need Some Help Figuring Out How to Use the PDSP2112

    It looks good Dan. Don't put yourself down like that. There's a lot to learn. You're doing fine.
  7. KrisBlueNZ

    Is this switch safe? Dual 26650

    Yes there's a mistake in your circuit. The pushbutton is connected straight across the batteries. Also the "coil" at the top is permanently connected across the batteries. You need to connect them all in series. But... Your battery voltage is 7.6V nominal (two 3.8V cells in series). If your...
  8. KrisBlueNZ

    FM modulator light only and no transmitting

    The second board in post #46 looks like it might work. It uses a 78M05 regulator which is not as immune to automotive voltage spikes as the transistor would be, but you can try it. Connect the white wire to the "RF" terminal, the red wire to the "5V" terminal and the black wire to the other...
  9. KrisBlueNZ

    Need Some Help Figuring Out How to Use the PDSP2112

    Sorry, I didn't notice that you'd separated out the two subroutines. That's good, though I think it would be better to call the first subroutine write_sr or something like that, not display. Also at the start of your shift register bit loop, you are setting SDI high or low according to the...
  10. KrisBlueNZ

    Relay Buzzing

    That diode is exactly right, but those bridge rectifiers are quite a bit bigger and their wire leads may not fit easily. Here's an exact match to the original: http://cpc.farnell.com/_/am151/bridge-rectifier-1-5a-100v/dp/SC07472
  11. KrisBlueNZ

    Relay Buzzing

    The bridge rectifier looks like a W01 which is rated for 100V, 1.5A. Suitable replacement is http://www.maplin.co.uk/p/kbpc104-2a-bridge-rectifier-aq99h The three diodes look like 1N4001 but to be safe you can use 1N4004: http://www.maplin.co.uk/p/1n4004s-1a-silicon-rectifier-ql76h
  12. KrisBlueNZ

    Fire hazard with small DC motor jamming?

    Also consider PTC resettable fuses. These get hot when they go open circuit, so they need to be mounted somewhat off the board and with nothing flammable close to them, but they're widely used and convenient because they reclose automatically when power is removed. See...
  13. KrisBlueNZ

    Relationship between Frequency, Inductance and Resistance

    I know. I was posting the article to make it easy for others to see what you're asking about, without having to go to the site and assemble the article text and the schematic, which are in separate locations on the EDN site. And I told you that I don't know the answer to your question.
  14. KrisBlueNZ

    How to wire 5 pin Jack

    Look at the first question on that product page. Each channel has one pin for the contact that touches the plug, and a second pin for a "switched" contact, which normally connects to the first pin but disconnects when the plug is inserted. In some cases, this enables you to switch the signal to...
  15. KrisBlueNZ

    Relationship between Frequency, Inductance and Resistance

    Here's the complete article as a single image: I don't know the answer to your question. I guess the 50 in the formula relates to the values of RL and RR in the schematic.
  16. KrisBlueNZ

    Multimeter fault UT136

    That should be fine. And you're sure the 555 is oscillating? Do you know the frequency and duty cycle, roughly? Does the meter simply display 0 for the frequency? There could be a fault but without a schematic it wouldn't be feasible to locate it.
  17. KrisBlueNZ

    Project Logs

    I think I like options 3 and 4 best, and option 1 least. But I'm concerned that there won't be enough interest to justify the work required to implement option 4.
  18. KrisBlueNZ

    LED Par Can schematic needed..

    So it seems that a "par can light" is a light in a large metal can, used for stage lighting etc, with a parabolic reflector. (I guess an LED version wouldn't have a reflector, but would be in the same style.) And DMX is an RS-485-based serial protocol that's used to control stage lighting and...
  19. KrisBlueNZ

    Relay Buzzing

    Wow, that's the proverbial can of worms! Rather than try to follow all those wires, can I suggest a simple experiment. Add a 2200 µF, 35V electrolytic capacitor (http://www.maplin.co.uk/p/2200f-35v-85c-radial-electrolytic-capacitor-vh55k) across the + and - terminals of the bridge rectifier...
  20. KrisBlueNZ

    Multimeter fault UT136

    What signal are you putting into it? Have you read the comments under the following review? Someone says frequency "doesn't work"; perhaps they didn't use a high enough input voltage.
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