Search:

Type: Posts; User: Zak28

Page 1 of 20 1 2 3 4

Search: Search took 0.01 seconds.

  1. Closed: Re: can triacs rapidly switch AC into a transformer

    This seems far more simple and practical. It would need a ballast or other current limiting element. Do SMC rectifiers typically fail short or open?

    154429

    There are tesla coil diagrams...
  2. Closed: Re: can triacs rapidly switch AC into a transformer

    If this is the suggested MOSFET switch, what is gate driver lowside common to? Or there is a better MOSFET topology.

    154427
  3. Closed: Re: can triacs rapidly switch AC into a transformer

    I thought light dimmers switched the current quicker than mains frequency.

    Would there be a workable solution implace of thyristors to have the high frequency?
  4. Closed: can triacs rapidly switch AC into a transformer

    Can a triac thyristor chop standard AC mains into 1-20Khz to transformer step up voltage as higher frequency than standard mains frequency?

    There might already be applications for this but Im not...
  5. Replies
    3
    Views
    218

    Closed: parasitic coil capacitance from frequency

    Sweeping a coil with generator measured a coils voltage peaking at ~30.7Mhz and dipping at ~14Mhz - its inductance is ~4mH.

    Does this mean its parasitic capacitance is 6.71 fempto farads?
  6. Closed: Re: measuring slow oscillations with magnetic methods

    Going to use a sub 5mm diameter magnet. Considering attaching a toothpick onto drill chuck and unwinding 28awg wire onto it.
  7. Closed: Re: measuring slow oscillations with magnetic methods

    How much does center hole diameter of an air coil crossover inductor coil type matter for picking up the oscillations?
  8. Closed: Re: measuring slow oscillations with magnetic methods

    They seem to be employing non semiconducting lasers. https://www.ligo.caltech.edu/page/ligos-ifo

    What are the minimum building blocks for mentioned ultrasonic method?
  9. Replies
    9
    Views
    528

    [SOLVED]Closed: Re: calculating capacitance of transistor gates

    Is Rgate the series resistor between gate driver output and transistor gate?
  10. Replies
    9
    Views
    528

    [SOLVED]Closed: Re: calculating capacitance of transistor gates

    This was to determine peak Igs current for gate driver which is 7.93nF for mentioned part.
  11. Replies
    9
    Views
    528

    [SOLVED]Closed: Re: calculating capacitance of transistor gates

    Hence max gate charge was determined at 415Vds was to obtain Vgs capacitance to obtain peak current which apparently is 7.93nF for 15Vgs at specified Ids.
  12. Replies
    9
    Views
    528

    [SOLVED]Closed: calculating capacitance of transistor gates

    Is it as simple as C= V/Q for this part maximum gate capacitance at 15v would be 119e-9/15 yeilding 7.93nF?

    https://i.ibb.co/7X79xqL/img.png
    ...
  13. Replies
    5
    Views
    348

    [SOLVED]Closed: Re: whats hfe during peak current

    Isn't the base 3.3amps much greater than 1/10th 10A going into the collector? Even if 1:10 base - collector current is only rule of thumb its very much disproportional for the mentioned 2n3055.
  14. Replies
    5
    Views
    348

    [SOLVED]Closed: whats hfe during peak current

    A BJT totem pole can be used in variety or circuits however is the current gain of BJTs (hfe) typically lower when Ice and Vce are greater?

    This being for sot-89-3 BJTs as the vast variety of...
  15. [SOLVED]Closed: More current from multi channel opamp buffer

    Would ganging all channels of an LM324 to buffer +/-5v from a dual supply ~25mA per channel cause its high frequency performance to drop? There are specialty buffer opamps but I only need =<1Mhz....
  16. Replies
    6
    Views
    870

    Closed: Re: obtaining thermal rise in diode

    This diodes junction will be 75C + ambient temperature while averaging 5amps?
  17. Replies
    6
    Views
    870

    Closed: obtaining thermal rise in diode

    This diode specifies Average Rectified Output Current @ TT = +75°C but referencing the If - Vf graph Figure 2 its Vf for 5A is ~1.15v power dissipated is 5.75W and Junction to lead thermal...
  18. Replies
    37
    Views
    1,313

    Closed: Re: tda2030 amplifies noise

    Boards enroute will be assembled in short order. Very likely =>16Vcc will alleviate noise from output.



    Apparently the carefully implemented and disguised free energy generators of the 80s in...
  19. Closed: Re: measuring slow oscillations with magnetic methods

    Couldn't an interferometer be devised from a high powered low junction capacitance IR led and a high speed LED transistor with the emanating LED and receiver each in an enclosed opaque tubing or is...
  20. Closed: Re: measuring slow oscillations with magnetic methods

    Are there non invasive methods aside from infared? The MEMS sensor requires mounting onto object, they are ideal for several measurements and infact are ideal for lateral displacements such as found...
  21. Replies
    37
    Views
    1,313

    Closed: Re: tda2030 amplifies noise

    Why would a pot of this arrangement need its 3rd pin grounded which would draw current thru the entirety of the 200R resistor into ground making no use of it? The 200R pot was selected to demonstrate...
  22. Closed: Re: measuring slow oscillations with magnetic methods

    Acoustic and mechanical movement are very related. This case its mechanical oscillation which requires specialty pick ups since they don't output typical acoustical frequencies.

    The nice object...
  23. Closed: measuring slow oscillations with magnetic methods

    Need to obtain natural oscillation frequency for several fr4 boards and other non PCB objects. Striking the objects emanates low frequency tone which dampens out rather quickly. The trouble with...
  24. Replies
    37
    Views
    1,313

    Closed: Re: tda2030 amplifies noise

    Its not the iCs, the're authentic. Whats the typical RMS volts into the non inverting pin for this single supply amp?

    Is this a decent filter or can values be improved?
    ...
  25. [SOLVED]Closed: Re: does copper tape need grounding when sheilding plastic enclosure

    Is it ineffective without grounding?
Results 1 to 25 of 490
Page 1 of 20 1 2 3 4