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  1. D

    Positive and Negative regulators sections are different

    I thought regulators had a current pass transistors internally inside the IC chip they have the current pass transistors externally A lot of times I don't even see current pass transistors in regulators circuits, any advantages of using current pass transistors? because mostly they leave them out
  2. D

    Comparators with diodes on the output why?

    ORed together how so ? i don't see it The comparator goes high or low, how does the diodes make the comparators output ORed?
  3. D

    Transistors switch on output pin or input pin

    When u guys say "tracking" u mean the VBE voltage change up and down the same, they are in union with each other? When transistors i found were fluctuating in voltage was because the VBE junction was bad The transistors collector pin voltage would be fluctuating because of the VBE junction...
  4. D

    Comparators with diodes on the output why?

    I don't understand why there is diodes on the output of these comparators? any reason Is it about sinking and sourcing current? Because a comparator with switch from a low state to a high state, so the diode does what?
  5. D

    Positive and Negative regulators sections are different

    here is another schematic that has the negative regulator that is different compared to the positive They use the inverting input of a 741 to invert the voltage But what is Q6 and Q17 doing? Why doesn't the positive regulator has this type of circuit like Q6 and Q17 It seems like Q5 just...
  6. D

    Transistors switch on output pin or input pin

    If there was no transistor on the output pin The output voltage and current would source? or sink? Or how would it source? Yes true , i have seen this
  7. D

    Transistors switch on output pin or input pin

    Here is a snip of a schematic which actually has transistors used as switches on the output pin of a Op amp comparator Any reason why they would use these transistors on the output pin of an op amp comparator? To make sure there is no leakage on the output pin? the transistors switch sinks the...
  8. D

    Transistors switch on output pin or input pin

    I'm trying to find the schematic, mostly i just got snippets on my camera of parts of schematics which i thought i didn't know how it worked I still not sure what u mean by this tracking? what do u mean by tracking Yes i know , because germanium transistors are worse with temperature varying...
  9. D

    Transistors switch on output pin or input pin

    How are these transistors temperature compensation? how so ? and when When the current gets to hot and warm for being left on for hours ? or when current gets higher in the current? Tracking what? how are transistors tracking
  10. D

    What kind of relay is this?

    Right the diode Clamps/limits the relays coils voltage when the switch is turned off
  11. D

    What kind of relay is this?

    Yes I have seen a zener diode in series, it's to protecting and stopping a negative voltage from the relay coil from entering into the circuit
  12. D

    What kind of relay is this?

    So it's an AC voltage that is charging or energizing the relay coil? The Relay coil itself has to be an AC relay coil? I didn't know where was DC relay coils and AC relay coils What you mean by how it can handle the VCC + Vz? The relay coil rises by the zener voltage? how can a zener...
  13. D

    Transistors switch on output pin or input pin

    Above or below? i was thinking it was below the output of the first op amp not above Yes true explain more about your theory, the op amps inputs are? or don't have? I was thinking the transistor is just "clamping" the op amps input
  14. D

    Transistors switch on output pin or input pin

    They are using the transistor like a variable diode right? Transistor#1 Because the transistors base is grounded , they are just using the emitter and collector Transistor#2 They tried the the base and collector to VCC So they are using just the emitter to base internal diode inside the...
  15. D

    Transistors switch on output pin or input pin

    Yes true, but they are using the transistor like a diode? or a variable diode
  16. D

    What kind of relay is this?

    So you're saying that the diode sinks and drains off into the supply very fast The cap stores the energy and sinks and drains off the flyback energy slowly back into the supply Does the capacitor and resistor limit the "undershoot voltage"? or just the diode clamps the undershoot voltage...
  17. D

    Transistors switch on output pin or input pin

    I thought a to make a log amp, was to put a transistor in the feedback loop not on the output pin So the Transistor is acting like a diode to "clamp" the input voltage? to limit it to not overload the input?
  18. D

    Measuring 800hz ripple looks like noise

    Yes True, The only time i have used the bandwidth button on my analog and digital oscilloscopes was when i was measuring AC ripple When have you used the bandwidth button? for what kind of measurements I'm going to try using an Analog Oscilloscope when measuring AC ripple and see if i get a...
  19. D

    What kind of relay is this?

    Williamson is not me arouse1973 , i don't know who that is So the cap across a diode increases or decreases the diodes inductance? what does the diodes inductance do to the flyback? or relay coil? What makes a hard suppression network? and what makes a soft suppression? I'm new to...
  20. D

    Test Fixture patch bay Diodes?

    On test fixtures , they have a patch bays that has multiple jacks on the front panel What does these diodes do? the diodes are in series If you plug the wrong jacks together, how does these diodes protect the text fixture? If a tech injected a Positive voltage into a jack , how would a...
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