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  1. Closed: Re: Embedded project needs devices which can work continuously at +125 degree C

    The MAXIM data sheet explains the interface, it is basically SPI with no data input pin as the device is read only.

    The SCK is always an input to the device and you can share the same signal...
  2. Closed: Re: Embedded project needs devices which can work continuously at +125 degree C

    You only need one pull-up on each shared line. I'm not sure why you use the 74HC151 like that, to me it would make more sense to use a 3 to 8 decoder (74HC138 for example) and use it to select one...
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    Closed: Re: Synchronous motor starting issue

    More information needed:

    Those motors only need sufficient AC voltage to make them turn, as long as you are using a reasonable frequency (50Hz or 60Hz) they should work fine. However, what you...
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    Closed: Re: Can anyone help with this Tesla coil?

    Just swap the connections to the thick black primary coil. Take the white wire and the green wire and connect them to the opposite ends of the black coil.

    A simple oscillator like that works...
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    Closed: Re: Can anyone help with this Tesla coil?

    Most likely you have the primary winding the wrong way around. Try reversing the connections to the primary (transistor collector) side and see if that fixes it.

    Note that connecting batteries in...
  6. Closed: Re: RF Transmitter - Pulsing sinusoidal wave @ 10.5K Hz. Pulsed every 36ms

    That looks good. You have the wrong symbol for the MOSFET but we can see what you mean and the transistor I recommended is a 2N2222 not 2N222 but the basic design looks fine.

    Brian.
  7. Closed: Re: RF Transmitter - Pulsing sinusoidal wave @ 10.5K Hz. Pulsed every 36ms

    That is almost right. You need two more components, a resistor (10K will do) from the collector of 'SST' to +5V and a capacitor of about 1uF (not critical) across the VSS and VDD pins of the PIC.
    ...
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    Closed: Re: RF Detector not detecting cellular phones

    My apologies, it wasn't meant to be condescending.

    The point I was making is that at high frequencies, because the wavelength is shorter, the effect of wiring length becomes critical. Taking your...
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    Closed: Re: RF Detector not detecting cellular phones

    From an RF point of view, that is a complete disaster. You really need to understand the concept of wavelengths then closely look at the tracks around the RF front end. The track carrying signal...
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    Closed: Re: PIC18F and PWM problem

    We need to see the full code to be sure but as a guess I would say you have the watchdog timer enabled and are not resetting it. The result would be the IC shutting down and resetting in a loop.
    ...
  11. Closed: Re: Overvoltage to X2 capacitor in 60W offline flyback

    I think the more important question is where does the 580V come from?
    But yes, it should be suitable otherwise. With the exception of thermal stress which accumulates damage over time, very few...
  12. Closed: Re: Need to boost 10.5KHz RF transmission distance from 4" to ~25+'

    The instructables design will never work efficiently because the current in the loop will be very small. Using whatever method you want to generate the signal, use a two transistor driver stage,...
  13. Closed: Re: RF Transmitter - Pulsing sinusoidal wave @ 10.5K Hz. Pulsed every 36ms

    PIC10F200 is the device number, it is an 8-pin microcontroller (or 6-pin in SMD package) and the smallest and simplest of all the Microchip MCU range. The difference in cost between 10F200, 10F202,...
  14. Closed: Re: ESD problem solved by using aluminium covered floor tiles?

    Your workbench is supposed to be grounded via 1M already.

    https://www.rapidonline.com/bjz-c-204-001h-esd-conductive-heel-strap-one-size-blue-51-8534
    (But don't forget to take your feet with you...
  15. Closed: Re: Turn on/off hall light with presence detection

    RFID fits all the requirements. All RFID tags have unique serial numbers which you can read so including or excluding a tag at point of entry is just a case of validating its ID.
    You can turn the...
  16. Closed: Re: ESD problem solved by using aluminium covered floor tiles?

    Look at it this way: You make an all metal conductive floor and charge it up to 100KV, on it you place a workbench and on the workbench you place your static sensitive devices. Will they be damaged...
  17. Closed: Re: Embedded project needs devices which can work continuously at +125 degree C

    I'm not sure about the flash, you would have to look closely at the ESP8266 data sheet to see if the timing and page layout is compatible. The one on my ESP8266-01 boards is branded "cFeon" with part...
  18. Closed: Re: Embedded project needs devices which can work continuously at +125 degree C

    Being practical, I would first try some pre-assembled ESP8266 boards at high temperature. Yes, that crystal will work but the chances are one very similar is already mounted on a pre-built module....
  19. [SOLVED]Closed: Re: Thermal sensor of a FAN cooler: Needed to identify

    The web site is http://www.tayao.com.tw but I can't see that exact model listed. Their catalog is a 17Mb download which would take ages here on my internet connection but yours might be faster.
    ...
  20. Closed: Re: Embedded project needs devices which can work continuously at +125 degree C

    Trimmers are relatively expensive and require manual adjustment using a DVM to monitor the voltage. If it is necessary to cater for both batteries and both fans, it would be cheaper to use one fixed...
  21. Closed: Re: Embedded project needs devices which can work continuously at +125 degree C

    You probably don't need the potentiometers, the values are predictable so you should be able to use fixed resistors.
    I note you have no over-current protection on the battery charging regulator....
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    Closed: Re: CLT1310079B and PIC16F1947 the same MCU?

    It is quite likely the same device but pre-loaded in the factory with a specific program for Yamaha. Microchip provide a service where they provide the devices out of the factory with the customers...
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    Closed: Re: Ac motor speed control

    venkates2218, I think your problem is not understanding how triacs and SCRs work. Think of them as a switch you turn ON with a pulse at any time there is a voltage across them but you cannot turn...
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    Closed: Re: AVR: SPI using interrupt

    Easyrider83 is being a bit harsh (and does not have the ability to ban users!).

    His comment is quite right though, it is very bad practice to add delays to an ISR. An ISR needs to react quickly...
  25. Closed: Re: Anyone please help identify what component is this with t4N marking code?

    The only component in SOT23 package with 4N as it's code that I can find is a transistor L2SC4083. It is described as an audio transistor but I can't find a datasheet.
    Note: it is NOT the same...
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