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  1. Sunnysky

    Powering 104 LED's from Molex connector, possible?

    It seems these 5mm white LEDs are good direct across a CR2032 which has an ESR, when new, similar to the LEDs around 15Ω. This pack starts at 12.6V not 12V Using my experience, if it looks OK on one CR2032, it probably is only using 10mA from a loaded cell around 2.9V. But that's Li not LiPo...
  2. Sunnysky

    Was, Were, Wasn't and Weren't

    "that the last big solar event was in 1858. Transformers melted, and telegraph stations were set on fire." That was called a Carrington event, by the observer's name. It has to do with Jupitor's massive magneto-gravitation effect on triggering bigger effects on the sun's surface which causes...
  3. Sunnysky

    GPS NMEA, Failover Circuit upgrade attempt.

    which clock do you need to be precise? The ToD digital sequence or the 1pps clock or 10MHz?
  4. Sunnysky

    Do you have experience with this product

    only$20 less than new. warranty?
  5. Sunnysky

    Hello everybody, thinking of buying this... What are your thoughts.

    Free movies and TV seems to be limited to 1080p for now. So 55" Hitachi 1080p on my PC or Android TV box with KODI and WMC for free local OTA digitalTV suits my needs. Just a a coffee table between the TV and leather sofa which has 2 recliners, makes me feel like I have IMAX . I'm sure 4K...
  6. Sunnysky

    Do you have experience with this product

    looks like an 8 zone wireless switch with relay switch outputs. you supply the plumbing and power solenoids. not much rain here, so the smart thing is find the minimum water to keep it alive.
  7. Sunnysky

    Passive sign convention

    There is no doubt the total power transferred is 60W. But by convention P= + for load and - for supply. The voltage sources with current flowing in (+) convention regardless if a generator, battery or PSU appear as a load, however batteries undercharged, may store energy as this load...
  8. Sunnysky

    Usb car radio

    The IC failure probably causes the regulator to overheat. ESD failure or supplier sent a dud? Although there looks like a solder splash on the corner pins near the black wire.
  9. Sunnysky

    Passive sign convention

    I would say the power sources are -50W and -10W while the power sinks or loads are +40W and +20W. Where passive power dissipation is positive. edit I could have been doing it wrong for 40yrs, so I checked. https://en.m.wikipedia.org/wiki/Passive_sign_convention
  10. Sunnysky

    Are optical power and electrical power directly comparable?

    If starting with 3dBm optical and splitter drops 11 dB ( to -8dBm) with cable loss say 12dB ( to -20 dBm = 0.01mW) Detectors are usually 0.5A/mW with transimpedance amps. Meanwhile 72dBμV is ~ 4mV in 75 Ω ~ -37dBm hmm
  11. Sunnysky

    Infrared Remote Control

    IR emitters can work by bouncing off walls if aimed properly and battery is good But 3 emitters gives better spread as they tend to be low beamwidth e.g. +/-10deg) Most are single these days, so it may be difficult to find. 3 requires more battery voltage as they tend to pulse 100mA and run...
  12. Sunnysky

    Are optical power and electrical power directly comparable?

    what emitter part number and efficiency? laser efficiency is low.
  13. Sunnysky

    Supply for 30 LEDs

    pretty soon , you will be going out to buy whole new emergency light and battery When in doubt measure, if it gets hot quickly, shut it off even faster. If battery is on float charge what is it? Now you do the math.
  14. Sunnysky

    Supply for 30 LEDs

    Bill? What was Vbat ? Was a charger on it? if so (7.2-3.6)V / 4.7 = 0.77A 3.32V * 0.77A = 2.55 W dissipated in LEDs = 95 mW *27 which exceeds LED power rating and thus excess current from excess voltage ... poof I^2R=P=2.8W Was it a a 1/4W resistor? poof ! In Ohm's Law you need to...
  15. Sunnysky

    What Is Happening Here?

    check your Vdc supply rails I looks like insufficient storage caps for low frequency power.
  16. Sunnysky

    Inverter

    let me get my crystal ball
  17. Sunnysky

    Yamaha MG16/4 mixing board

    ICG06 appears on a block diagram as one of the 4 bus buffers using dual Op Amps http://akizukidenshi.com/download/NJM4580.pdf Did this fail during cable hookup? ref. http://elektrotanya.com/cgi-bin/download2.cgi
  18. Sunnysky

    Supply for 30 LEDs

    Ok know measure Vled and Vbat. If I Assume Vled=3.1, Vbat=3.6 then ( 3.6-3.1)/15R= 333mA /27 then average current per LED is 12.3 mA is safe and will last longer but not full brightness. I think you can calculate this for desired Ah and current so it does not exceed 20mA per LED. Since power...
  19. Sunnysky

    Supply for 30 LEDs

    .15 OHm? for which battery? is that 29 LED's now?
  20. Sunnysky

    ADC0820 and drum pad

    Perhaps the switched S&H input capacitance needs a unity gain buffer near the input to ADC.
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