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  1. Sunnysky

    switching a relay - but on second switch. ( if that makes sense? )

    S1 Reset FF , Q=0 S2 trailing edge clocks a flip flop , D=1 then Q=1 when S2 closes AND Q=1 the. Q1-c output transistor turns off. THis can be inverted if desired or drive a relay Reed relays may need 100pF across inputs to suppress noise. 5V needs decoupling cap as usual. Q1 any NPN...
  2. Sunnysky

    switching a relay - but on second switch. ( if that makes sense? )

    the relays you show will not work as they need to be latching with twin coils.
  3. Sunnysky

    why would parasitic resonance defeat inductance?

    They do cancel at resonance , but above fo, the cap dominates the impedance by shunt or bypass.
  4. Sunnysky

    Help Identifying a Battery

    looks like CR123 with 2x in series exact dimensions would help
  5. Sunnysky

    LCD Screen won't display anything anymore on 400W LED Strobe Light

    was it ever used outdoors in humid or wet conditons? seems like a poor warranty. alibaba order? https://www.alibaba.com/product-detail/led-strobe-400-for-professional-stage_60471066267.html?spm=a2700.7724857.0.0.r4Mnuk
  6. Sunnysky

    Question about PTC fuses

    SIze affects voltage and trip time as well as Rmin/max The main thing is choosing a trip time that protects your motor. Normally time is rated at a trip level that is 2x hold current . Here is a variety to compare...
  7. Sunnysky

    NASA MARINE TARGET 2 DEPTH NOT SWITCH ON

    so no sign of life? no method of calibration? damaged sensor?
  8. Sunnysky

    Relay Switching Problem

    You show a lack of attention to details, which leads be to believe you have major EMI crosstalk from coil or contact current getting into the logic. Without more details on layout, part numbers and grounding, there are too many things wrong. Try a small cap between ShReg input to ground,.
  9. Sunnysky

    LCD Screen won't display anything anymore on 400W LED Strobe Light

    it seems like a compatibility issue
  10. Sunnysky

    LCD Screen won't display anything anymore on 400W LED Strobe Light

    I hope it had a working fan during operation and they have a service centre.
  11. Sunnysky

    A website i made

    0, TOLERANCE :5%, 100PPM brown brown black gold gold brown hmm I would not use it
  12. Sunnysky

    Amp In Protection Mode

    that junction is your speaker output before the relay,,which needs to be null. Let's see what @dorke says. I've stated the 2 target parts that could be bad. My money is on Q603
  13. Sunnysky

    Frankenstein's Components.

    My son once took me to see an online friend of his in Ohio who had a garage full of surplus equipment from White Sands military base. He was the guy who demonstrated 80mpg on popular science long ago running off water. He used exhaust superheated steam injected into a carburetor in an old...
  14. Sunnysky

    Amp In Protection Mode

    right... the only high impedance part in this design which has near unity DC loop gain and AC gain of ~ 40 is the front end Q603. About 50k leakage across Vce will pull the output up to 7V. The AC gain permits 1Vp to reach 40Vp if the 1000uF does not have higher ESR yet. This failure mode...
  15. Sunnysky

    Frankenstein's Components.

    since you mentioned optical mice, I recall one laser mouse having such a sensitive detector to bring it out of sleep mode that when I inverted it, I found it detected a finger motion on the center axis 2 meters away. I think It does this by using a fresnel lens and interference patterns. Then...
  16. Sunnysky

    DC Bus in a Loop Configuration. Problem?

    The DCC. 2V pulses are 58us and 100us for 1 & 0. This spectrum includes 50kHz and harmonics up to 0.5 MHz or so. Brush motor noise covers many decades and exceeds this bandwidth but are lower amplitude than .2V if filtered when by the train when DCC is confined to this decade of signal. It...
  17. Sunnysky

    Microstrip Antennas Manipulation

    Delphi bought an RF company with the patent to tune stripline antenna with a diode as a varicap for auto tuning to different VHF bands in car garage door openers. But if this is for >1GHz you will have significant challenges even if you have a network analyzer and the experience using...
  18. Sunnysky

    Amp In Protection Mode

    Somehow I overlooked those readings. Then remove D605 clamp diode. If reverse leakage is high uA, it will pull up the output. changing feedback R641 to chassis 0v will only cause output to pull up all the way to 45V or so.
  19. Sunnysky

    switching a relay - but on second switch. ( if that makes sense? )

    If only the tip of the rod activates the reeds momentarily, it MUST do so in both directions for this logic to work, and at no other time in between. If this can be done, then the logic needed might use 1 FF and 1 NAND or AND gate. SW1 Reset FF , Q=0 SW2 leading edge clocks a flip flop , D=1...
  20. Sunnysky

    UL compliance leakage testing, GFCI

    If using AC HIPOT , filter caps must. be removed as filter leakage current to ground is proportional to Vcm-gnd HIPOT test. This is why DC HIPOT is better with 1.41* AC voltage. with a slow ramp. I recall 10% higher voltage permits a 1 second test vs long test. Then no caps need to be removed...
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