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  1. D

    Simple delay on

    One possibility : https://www.electro-tech-online.com/articles/pulse-sequence-generator-smart-timer.938/ Regards, Dana.
  2. D

    Tek 7L13 repair

    There are several Tek groups over here - https://groups.io/groups Regards, Dana.
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    Delaying low voltage pulse

    SAR = Successive Approximation Register A/D converter. Basically use a SAR to digitize / sample pulses, feed to a memory delay line approach. Analog delay possibly use a CCD approach : https://mysite.du.edu/~etuttle/electron/elect39.htm...
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    Delaying low voltage pulse

    I concur, I had thought axis label was uS. I should have known better. Tektronix in their old scopes used delay lines and they were high order and only capable of nS delays. My apologies. I think lumped element delay lines simply out of the realm of possibilities. Note if this is what you want...
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    Delaying low voltage pulse

    A pulse as you know has many frequency components : The freq of a p[use train is 1 / period. An allpass, ideal, will replicate the waveshape of the pulse. Real allpass are approximations, so amplitude and waveshape are affected. Basically you make a tradeoff between complexity and fidelity in...
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    DIY burglar alarm

    The manufacturer must have a driver to go with board to install it..... What chips are on board ? Part numbers ? Regards, Dana.
  7. D

    Help to ID capacitor (laptop)

    its 220 uF 6.3V. Use a mic to get size and pinout spacing when you go looking. Unless someone else recognizes this series go to AVX website and post pic for recommendation. It may have certain ESR properties that need to be addressed. https://www.kyocera-avx.com/products/aluminum-capacitors/...
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    How Do I Use This Device

    Consider using ESP8266 or ESP32. https://robotzero.one/sending-data-esp8266-to-esp8266/ https://www.instructables.com/The-Easiest-Way-to-Send-Data-From-ESP8266-to-a-Web/ https://randomnerdtutorials.com/esp8266-wireless-weather-station-with-data-logging-to-excel/ As far as range -...
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    DIY burglar alarm

    As an aside this might be of interest, shows how easy it is to do speech generation. Requires an Arduino tethered to PC thru USB. https://www.edaboard.com/threads/gui-codeless-processor-design.397358/#post-1708529 Regards, Dana.
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    How Do I Use This Device

    Some comments here - https://forum.hobbycomponents.com/viewtopic.php?f=74&t=1473 There are other posts there as well on this module. Regards, Dana.
  11. D

    Delaying low voltage pulse

    Note the bessel filter is not an allpass but exhibits approximate linear phase over a range of frequencies. , So you would not pass the wave shape unaltered over a wide range of frequency, you tradeoff delay versus fidelity of pulse...
  12. D

    How Do I Use This Device

    What are the part numbers on the two chips ? Link to ebay item for sale ? Regards, Dana.
  13. D

    Delaying low voltage pulse

    Bessel (allpass) filter : https://rf-tools.com/lc-filter/ You would have to change design criteria to get the 1-2 uS you want. Regards, Dana.
  14. D

    How to build a charge amplifier with fC resolution and low bandwidth?

    There are OpAmps with much lower Ibias than you are using ...
  15. D

    is this bjt transistor hbridge right?

    You can directly drive the L298N from Arduino, no R needed : As you can see very small current needed by inputs. What are your motor specs in terms of V and I ? Regards, Dana.
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    is this bjt transistor hbridge right?

    Low cost H Bridge that will interface to Arduino -...
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    JFET "Amplifier". How Would This Work?

    I see the fdbk is negative as you point out. Here is a crude sim - I dropped Rl to 50 ohms, gate starting to go +, clamping, not good for JFET. At Rl = 200 ohm problem goes away. Regards, Dana.
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    JFET "Amplifier". How Would This Work?

    Depending on polarity could be + fdbk (oscillate) or - fdbk, amplify. If it was oscillator why the need for input signal.....produce a damped ringing..... Too little info = too much guessing....:) No other clues in his notebook......? Like what was it used in, a toaster or a tricorder...
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    JFET "Amplifier". How Would This Work?

    "Normally" one parallels devices to increase current delivery / power handling capability. Whats confusing with the drawing is test signal is not RF, yet the air wound coil, few turns, and fact 2N5670 is a small signal JFET implies its a RF amp. Then there is transformer with no polarity...
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    is this bjt transistor hbridge right?

    You do not want top and bottom transistor in same leg to turn on at same time, thats key. Otherwise you have a dead short on the power supply to ground. Thats usually taken care of in embedded processor PWM settings or in external driver chip. Most scopes can measure that time delay. No on...
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