1. Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
    Dismiss Notice

Question for the Oscilloscope Experts

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by rsfoto, Oct 10, 2015.

  1. audioguru

    audioguru Well-Known Member Most Helpful Member

    Joined:
    Mar 16, 2004
    Messages:
    32,437
    Likes:
    933
    Location:
    Canada, of course!
    Since I got the lenses in my eyes replaced due to cataracts I can see everything as clearly as your photos of the moon.
     
  2. Mosaic

    Mosaic Well-Known Member

    Joined:
    Jun 3, 2010
    Messages:
    2,569
    Likes:
    128
    Location:
    Caribbean
    Can anyone spot an Apollo LEM base in that pic?
     
  3. rsfoto

    rsfoto Member

    Joined:
    Jun 14, 2013
    Messages:
    189
    Likes:
    9
    Location:
    Mexico
    Which of all ?

    :p

    BTW I have a bigger Mosaic but it is not full moon

    You can see it here http://astroforo.net/astro/moon/Moon1.jpg and it is about ~ 8363 pixels wide and high
     
    Last edited: Dec 25, 2015
  4. dave

    Dave New Member

    Joined:
    Jan 12, 1997
    Messages:
    -
    Likes:
    0


     
  5. Mosaic

    Mosaic Well-Known Member

    Joined:
    Jun 3, 2010
    Messages:
    2,569
    Likes:
    128
    Location:
    Caribbean

    The one with the double parked rover...8)
     
    • Funny Funny x 1
  6. rsfoto

    rsfoto Member

    Joined:
    Jun 14, 2013
    Messages:
    189
    Likes:
    9
    Location:
    Mexico
    Talking about my circuit again. Somehow I saw something about bypass capacitors on the supply pins. Would it do some good to implement them in my circuit ?

    Thanks
     
    Last edited: Dec 26, 2015
  7. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

    Joined:
    Oct 30, 2010
    Messages:
    9,910
    Likes:
    1,095
    • Thanks Thanks x 1
  8. audioguru

    audioguru Well-Known Member Most Helpful Member

    Joined:
    Mar 16, 2004
    Messages:
    32,437
    Likes:
    933
    Location:
    Canada, of course!
    Every transistor circuit and IC must have a decoupling capacitor very close to the supply pins of the IC or circuit. Your TL081 opamps have some voltage gain as high as 3MHz so they need high frequency ceramic decoupling capacitors (47nF or 100nF) to prevent high frequency oscillation and your circuit probably needs low frequency 47uF or more electrolytic decoupling capacitors to smooth low frequencies.
     
    • Thanks Thanks x 1
  9. rsfoto

    rsfoto Member

    Joined:
    Jun 14, 2013
    Messages:
    189
    Likes:
    9
    Location:
    Mexico
    Hi,

    Yesterday it looked like I made a major step forward in that sense that I saw sometimes no longer a peak bottom curve over a period of time but saw a longer peak curve. Looks like the simple LP filter I have using 100ηF capcacitor and a 100K resistor is working from time to time but on very selective vibrations of my working desk.

    Today if I have time I will build a Sallen- Key LPF and integrate it into the circuit.

    All the supply pins do have now a 47ηF capacitor. Somehow I got the impression the output looks better. Will keep you informed.
     
  10. audioguru

    audioguru Well-Known Member Most Helpful Member

    Joined:
    Mar 16, 2004
    Messages:
    32,437
    Likes:
    933
    Location:
    Canada, of course!
    100k ohms feeding 100nF to ground makes a simple lowpass filter that is -3dB (0.707 times) at 16Hz. Its level is -12dB (0.25 times) at 64Hz so it noticeably reduces electrical interference and at the sensor resonance frequency of 75Hz it flattens the resonance.
     

Share This Page