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    555 Trigger

    I will double check the voltage and resistor values when I get to work today.
  2. P

    555 Trigger

    OK. Condenser mic AKA electret mic AKA electret condenser mic. The output waveform is severely clipped. It generates a spike. The ADC constantly reads the voltage on it and any change detected makes an output high. I never tried it but the spike could possibly trigger a 555. I don't understand...
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    555 Trigger

    We've been using this. It feeds a uC ADC input and can pick up a whisper 10 feet away.
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    IR sensor OR something else?

    This thread sounds very familiar. Let me repeat the advice I gave a while back. Why don't you just look at the casing before you seat the bullet like I used to? Using a homebrew setup with cameras, sensors and a servo motor requires electricity. Electricity can cause a spark. With smokeless...
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    Wanted: Looking for a GE NX-148E Keypad Version 4.09

    Welcome to the forum. They are available on ebay.
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    LTC6806 Availability

    Welcome to the forum. Check this link for a description: https://www.arrow.com/en/products/ltc6806hlw3zzpbf/analog-devices?utm_term=backorder&utm_currency=&utm_campaign=arrow_findchips_2021_Americas&utm_medium=aggregator&region=nac&utm_source=findchips&utm_content=inv_listing
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    Tracking and layout help

    https://www.4pcb.com/trace-width-calculator.html
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    Wanted: Microchip Technology USB2514B or USB2514BI

    https://www.chip1.com/rfq/find-chips?partno=USB2514B-AEZC&utm_source=findChips&utm_medium=submitRfq 44 pieces in stock
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    Small motor with 104 cap bridge between terminals.

    A 0.1uF (104) cap is mandatory on our products that use LV motors. Sometimes we add a 10uF electrolytic in parallel for the most sensitive circuits.
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    OOPS! I MEAN BIG OOPS, MAYBE. ROOKIE MISTAKE

    It had a telescopic whip antenna 6 inches from my forehead. And I believe what the ICNIRP is referring to is constant exposure. Living, sleeping, eating, bathing in a house that is constantly emiting RF is one thing but draping test leads over a leg while working on an audio amplifier is, what I...
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    OOPS! I MEAN BIG OOPS, MAYBE. ROOKIE MISTAKE

    Hank, I was reading up on exposure effects of RF. Negative effects have been reported by RF at very high frequencies and at very high power levels. Your 2N3055 may pass a few MHZ but certainly not at any appreciable power level. Back in the 1970's I had a 5 Watt CB walkie talkie which I...
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    Possible to control resistance using microcontroller?

    Sorry - I missed the LED driver thing but have had success in the past driving the display directly from the uC.
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    Possible to control resistance using microcontroller?

    Welcome to the forum. A uC with a PWM can control the brightness by supplying power to the common LED pin. An LDR could also be used on a uC ADC input to vary the brightness with respect to ambient light in the room. What uC are you using?
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    Resistor Array Identification

    Welcome to the forum. I believe this is a 100K 2% resistor network. I don't know if it isolated or common bus. Why do you want to know the manufacturer? Do you think this part is bad?
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    Small motor with 104 cap bridge between terminals.

    104=0.1uF. 103=.01uF.
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    SONY TA-212 STEREO AMPLIFIER

    Welcome to the forum Ivan. I looked at the schematic and saw that this potentiometer has a tap in it's resistance. This is going to be a hard one to find. What makes you think it's bad?
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    What is the difference between 2SA1943 and TTA1943?

    The 2SA1943 and 2SC5200 are both rated 250V, 17A. The TTC5200 is 230V, 15A. You can easily google these for the datasheets.
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    Logic Gate Sanity Check

    I use a PIC16F73 to feed 2 PWM outputs to 2 MOSFETS.
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    Need help with photocell stats

    Welcome to the forum. I believe you are referring to an LDR (light dependent resistor). A couple of questions: what is the purpose/function of this part? Do you have a part number for the original? My LDR of choice is a 5528. It has a wide swing of resistance from 8-20K in light to a minimum of...
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    Problem with multimeter DT9205A

    Welcome to the forum. Something must be toasted inside but not visibly. For less than $10 you can buy a new one...
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