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    What kind of relay is this?

    What kind of relay type is this? What tool would you guys use to get them out of the sockets When I used pilers, it squeezed the chassis of the relay and smashed it There is too many components around the relays to get a flat head screw driver underneath it, it lift it out
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    Measuring the Low state of TTL, CMOS , Pulses

    Here is the pictures Picture Pic#1 is what the low state looks like Picture Pic#2 is when i increase the voltage per division more Picture Pic#3 I increase the volts per division more Picture Pic#4 I increase the volts per division more It adds more and more noise , plus it slants,slopes...
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    Measuring 800hz ripple looks like noise

    This is 120hz ripple, this is what i'm use to seeing as a ripple waveform , it's sawtooth like I think ripple should only look like this , take a
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    Measuring 800hz ripple looks like noise

    400hz and 800hz ripple pictures I still can't believe this is ripple, it looks like noise to me , take a look
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    Measuring the Low state of TTL, CMOS , Pulses

    The output pin of op-amps and logic gates should be low impedance I will upload the pictures tomorrow , I don't have my camera adapter right now but i do have the pictures taken you will see the noise and the slope/ramp it makes when you adjust the voltage per division on the O-scope when...
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    Measuring the Low state of TTL, CMOS , Pulses

    Why does the output rise when you put a load on it? that doesn't make sense Yes i know this I can't, because it's toggling or alternating from high and low state It's a Pulse train, I'm trying to measuring the voltage of the low state of a logic pulse train Logic TTL pulse train or a CMOS...
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    Measuring the Low state of TTL, CMOS , Pulses

    Why would it be normal? i don't get it You're saying that all TTL and CMOS logic chips don't output a low state at zero volts, why is that? any reason why they do that? How do you measure the low state of a TTL or CMOS chip? what is your ways of doing this The way i'm doing it is wrong
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    Measuring the Low state of TTL, CMOS , Pulses

    Why is that? I'm "zooming in" or using "window zoom" on my O-scope But it's magnifying noises How do you measuring the low state compared to the zero crossing point on the O-scope? how do u set it up Should i use a Digital volt meter instead to measure the low state of an TTL or CMOS low...
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    Measuring the Low state of TTL, CMOS , Pulses

    Yes true there is different threshold voltage for each logic families Yes i know, it's between the ground zero crossing to the first division , its in between I'm talking about very very small volts, so I have to zoom in No , I mean what would cause a Failure to have the TTL or CMOS low...
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    Measuring the Low state of TTL, CMOS , Pulses

    In volts But when "zooming" in on an O-scope of the Low states volts of a TTL or CMOS low state , the displacement from zero volts ground to the low state is in microvolts or millivolts but it can but to +/- 2 volts vdc The hard part is zooming in on an O-scope without getting all the noise...
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    Calculating gain in this op amp stage

    I would think putting a resistor in the Meg ohms would be a lot of gain, like a open loop gain, not a close loop gain
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    Measuring the Low state of TTL, CMOS , Pulses

    The displacement is in microvolts The Problem is trying to view the displacement from zero volts and the point of the low states voltage is at What would cause a TTL or CMOS low state to be at +1 volt or +2 volts?
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    Measuring 800hz ripple looks like noise

    Yes the output ripple of a 60hz power supply is 120hz ripple, looks like sawtooth waveform The output ripple of a 400hz and 800hz power supply looks like noise, it doesn't have the sawtooth waveform I didn't know ripple was an AC noise on a DC reference I thought ripple was an AC waveform...
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    Input impedance and Max RMS ac voltage

    True, but a single shot waveform time duration is measured in TIME I thought the inverse of time was frequency , so it must have a frequency What kind of time duration are we measuring? I think you mean to put a 50ohm resistor across the Red and black terminals of the universal counter I...
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    Measuring 800hz ripple looks like noise

    Measuring 800hz ripple from a power supply looks like noise I didn't know the output of a power supplies noise was ripple, I thought ripple was a sawtooth looking waveform 60hz ripple looks like a sawtooth waveform 400hz and 800hz ripple looks like noise When measuring Ripple: I'm using...
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    Measuring the Low state of TTL, CMOS , Pulses

    How do you measure the Low states voltage on TTL, CMOS or pulse waveforms? I have read that the Low states voltage can range from -2 volts vdc to + 2 volts vdc What would cause the Low state to go to -2 volts vdc? or to +2 volt vdc? I'm using a Tektonrix TDS 2022 I go to the Horizontal...
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    Calculating gain in this op amp stage

    So R114 sets up a biasing operational point? or how does it balance the input current? Why would they want a 2.15MΩ resistor in the feedback loop? this makes the gain stable? I don't see Meg ohms resistors in the feedback loop often in gain stages, I'm not sure why it's used and for what reason
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    Calculating gain in this op amp stage

    R116 is 2.15 megs, why use a Meg ohm resistor in the feedback? One tech said here that Meg ohm resistors are used as stablizers when the are "coupled" to other resistors or caps This R116 must be a stablizer? to stable the feedback or op amp
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    Input impedance and Max RMS ac voltage

    Are they called BNC attenuation boxes? or what are they called for electronic bench equipment to do attenuation for inputs like this? Also does frequency counters track low frequency better using a square waveform compared to sine waveform? Also, what is the advantage of using a frequency...
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    Input impedance and Max RMS ac voltage

    Thanks I will try the Coax cable instead of the red and black banana cables Since my frequency counter is 50ohms , Max 5 volts RMS If you're circuit under test needs a 10 volt peak, how do you get 10 volts peak ( 20 volts peak to peak ) on the O scope but also have the frequency counter...
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