+ Post New Thread
Results 1 to 16 of 16
  1. #1
    Junior Member level 3
    Points: 2,241, Level: 10
    Achievements:
    7 years registered

    Join Date
    Sep 2008
    Posts
    28
    Helped
    2 / 2
    Points
    2,241
    Level
    10

    Problem with using ic uA733

    Does anyone use uA733.The input signal is 30mv,17MHz.I expexted about 300mv.
    I sending schematic diagram.
    Bestregards.

  2. #2
    Super Moderator
    Points: 266,444, Level: 100
    Awards:
    1st Helpful Member

    Join Date
    Jan 2008
    Location
    Bochum, Germany
    Posts
    46,563
    Helped
    14168 / 14168
    Points
    266,444
    Level
    100

    Re: Problem with using ic uA733

    The input signal is 30mv,17MHz.I expected about 300mv.
    What is input signal in your circuit? How do you measure it? How should the problem be related to uA733?



  3. #3
    Junior Member level 3
    Points: 2,241, Level: 10
    Achievements:
    7 years registered

    Join Date
    Sep 2008
    Posts
    28
    Helped
    2 / 2
    Points
    2,241
    Level
    10

    Re: Problem with using ic uA733

    Quote Originally Posted by FvM View Post
    What is input signal in your circuit? How do you measure it? How should the problem be related to uA733?
    Hello again.I measured it with osciloscope.How is sed in datasheed, conecting leads
    11,4/or 12,3-this can give as all aplification coeficients.Output signal is lower than
    input.I cannot apmplifie this signal.By the way,signal is 40MHz not 17MHz.I made a mistake.
    Is it conection is wrong ot this circuit,has difficulties with aplification.In the datasheet is sed
    that they are up to 200MHz,but honsetly i am reserved.How can i decide the problem?
    I do not whant to conect a lot of tons uA733.Although leades are not conected together
    i mean 11,4 the amplification is 10.That means about 200mv in the output.
    Bestregards:Barosov/Bulgaria
    LZ6LB/73



    •   AltAdvertisement

        
       

  4. #4
    Super Moderator
    Points: 85,304, Level: 71
    Achievements:
    7 years registered
    Awards:
    2nd Helpful Member
    betwixt's Avatar
    Join Date
    Jul 2009
    Location
    Aberdyfi, West Wales, UK
    Posts
    14,038
    Helped
    4671 / 4671
    Points
    85,304
    Level
    71

    Re: Problem with using ic uA733

    What puzzles me is the pins of TX1 suggest it is a metal can package with pins to fit a 14-pin DIL profile. That almost certainly means it produces TTL level outputs. If I'm right, TX1 pin 8 should connect directly to the 'D' input of the flip-flop and the LM733 isn't needed at all.

    Brian.
    PLEASE - no friends requests or private emails, I simply don't have time to reply to them all.
    It's better to share your questions and answers on Edaboard so we can all benefit from each others experiences.



  5. #5
    Advanced Member level 4
    Points: 8,810, Level: 22
    Achievements:
    7 years registered

    Join Date
    Nov 2009
    Location
    Italy
    Posts
    1,195
    Helped
    406 / 406
    Points
    8,810
    Level
    22

    Re: Problem with using ic uA733

    From your schematic LM733 is supplied between 12V ad GND. The datasheet doesn't seem to say it can be used in a single supply configuration



    •   AltAdvertisement

        
       

  6. #6
    Super Moderator
    Points: 266,444, Level: 100
    Awards:
    1st Helpful Member

    Join Date
    Jan 2008
    Location
    Bochum, Germany
    Posts
    46,563
    Helped
    14168 / 14168
    Points
    266,444
    Level
    100

    Re: Problem with using ic uA733

    The datasheet doesn't seem to say it can be used in a single supply configuration
    Input is biased to mid supply, no problem.



  7. #7
    Junior Member level 3
    Points: 2,241, Level: 10
    Achievements:
    7 years registered

    Join Date
    Sep 2008
    Posts
    28
    Helped
    2 / 2
    Points
    2,241
    Level
    10

    Re: Problem with using ic uA733

    Quote Originally Posted by FvM View Post
    Input is biased to mid supply, no problem.
    Good morning.I have just returned from night shift.I have two resistor
    to provide midle power supply.The uA733 is conected according to data
    sheet.
    Bestregards:Barosov



    •   AltAdvertisement

        
       

  8. #8
    Super Moderator
    Points: 83,981, Level: 70
    Achievements:
    7 years registered
    Awards:
    Most Frequent Poster 3rd Helpful Member

    Join Date
    Apr 2014
    Posts
    17,075
    Helped
    3858 / 3858
    Points
    83,981
    Level
    70

    Re: Problem with using ic uA733

    Hi,

    May I ask why you use a differential amlifier when you just use one output?
    To measure gain you need to involve both outputs: Vout = VOut+ - VOut-

    Just to talk about the same datasheet: which amplifier exactly arou you using: LM733 or uA733? Which package?

    Klaus
    Please don´t contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



  9. #9
    Junior Member level 3
    Points: 2,241, Level: 10
    Achievements:
    7 years registered

    Join Date
    Sep 2008
    Posts
    28
    Helped
    2 / 2
    Points
    2,241
    Level
    10

    Re: Problem with using ic uA733

    Quote Originally Posted by KlausST View Post
    Hi,

    May I ask why you use a differential amlifier when you just use one output?
    To measure gain you need to involve both outputs: Vout = VOut+ - VOut-

    Just to talk about the same datasheet: which amplifier exactly arou you using: LM733 or uA733? Which package?

    Klaus
    ;*********************************************8888
    I am using uA733.I know if we using only one otput the amplifaing
    is a half.But output amplitude is lower that input only 20mv.That is fun.
    I want to understand where is the problem.I know that we cannot
    get otput about 2 or 3 volt with input-20mv in 40MHz,just with one chip
    we need minimum 2 or 3 chips.I want to understand why this chip
    doesnot want to aplifie.
    Good day.



  10. #10
    Super Moderator
    Points: 266,444, Level: 100
    Awards:
    1st Helpful Member

    Join Date
    Jan 2008
    Location
    Bochum, Germany
    Posts
    46,563
    Helped
    14168 / 14168
    Points
    266,444
    Level
    100

    Re: Problem with using ic uA733

    Can we please clarify the post #4 question. What's the oscillator type and has it really low output voltage in the 100 mV range, or even less?



  11. #11
    Junior Member level 3
    Points: 2,241, Level: 10
    Achievements:
    7 years registered

    Join Date
    Sep 2008
    Posts
    28
    Helped
    2 / 2
    Points
    2,241
    Level
    10

    Re: Problem with using ic uA733

    Quote Originally Posted by FvM View Post
    Can we please clarify the post #4 question. What's the oscillator type and has it really low output voltage in the 100 mV range, or even less?
    ;************************************************* ********88
    Yes we can clarify the post.This is the oscilator schematic.



  12. #12
    Advanced Member level 5
    Points: 15,691, Level: 30
    Achievements:
    7 years registered
    schmitt trigger's Avatar
    Join Date
    Apr 2013
    Posts
    2,607
    Helped
    835 / 835
    Points
    15,691
    Level
    30

    Re: Problem with using ic uA733

    Back in the late 80s I successfully built several video distribution amplifiers using the NE592, which is a exact equivalent of the LM733. It was single ended mode also.
    I am including the datasheets.

    I am also enclosing a snippet of the overall diagram.

    The differences that I see from your and my diagram:

    -I used a bipolar +/-6 volt supply, although your biasing configuration should also work.
    -I actually used the gain setting pins, which you are not.

    I would suggest that you solder a trimpot between gain adjust terminals G1a and G1b, as I am showing in my schematic.

    [/ATTACH][ATTACH=CONFIG]157973

    lm733cn.pdfNE592-D.PDF
    Last edited by schmitt trigger; 28th February 2020 at 18:41.
    My batteries are recharged by "Helpful Post" ratings.
    If you feel that I've helped you, please indicate it as a Helpful Post



  13. #13
    Junior Member level 3
    Points: 2,241, Level: 10
    Achievements:
    7 years registered

    Join Date
    Sep 2008
    Posts
    28
    Helped
    2 / 2
    Points
    2,241
    Level
    10

    Re: Problem with using ic uA733

    Thank's a lot for your help.What was the amplitude of the input signal
    of your shematic,and the freqwency?And what was the amplitude of output signal?
    Bestregards:Barosov
    LZ6LB.



  14. #14
    Advanced Member level 5
    Points: 15,691, Level: 30
    Achievements:
    7 years registered
    schmitt trigger's Avatar
    Join Date
    Apr 2013
    Posts
    2,607
    Helped
    835 / 835
    Points
    15,691
    Level
    30

    Re: Problem with using ic uA733

    It was NTSC video, meaning 4 Mhz and 2Vpp (drops down to 1 Vpp with 75 ohm termination)
    My batteries are recharged by "Helpful Post" ratings.
    If you feel that I've helped you, please indicate it as a Helpful Post



  15. #15
    Junior Member level 3
    Points: 2,241, Level: 10
    Achievements:
    7 years registered

    Join Date
    Sep 2008
    Posts
    28
    Helped
    2 / 2
    Points
    2,241
    Level
    10

    Re: Problem with using ic uA733

    Quote Originally Posted by betwixt View Post
    What puzzles me is the pins of TX1 suggest it is a metal can package with pins to fit a 14-pin DIL profile. That almost certainly means it produces TTL level outputs. If I'm right, TX1 pin 8 should connect directly to the 'D' input of the flip-flop and the LM733 isn't needed at all.

    Brian.
    ;************************************************* *****
    Hello Brian.
    TX1 is fabric oscillator with 4 pins.It gives about 200mv at 40MHz
    clear sinosuid.I made one amplifier with FET input and other four
    transistors.With other oscillator that give 30mv at 17MHz,it give me
    about 2 volts output signal.If you interested I can send you schematic
    diagram.I will experiment other schematic.I must do FLL system that
    lock the freqwency of the band generator for transiever.
    Barosov.



    •   AltAdvertisement

        
       

  16. #16
    Super Moderator
    Points: 85,304, Level: 71
    Achievements:
    7 years registered
    Awards:
    2nd Helpful Member
    betwixt's Avatar
    Join Date
    Jul 2009
    Location
    Aberdyfi, West Wales, UK
    Posts
    14,038
    Helped
    4671 / 4671
    Points
    85,304
    Level
    71

    Re: Problem with using ic uA733

    I would suggest using a comparator instead of an amplifier. The signal you need is to clock the logic devices, using a comparator will ensure you get a clean logic level output. If you use an amplifier you can get the amplitude you need but the edges will not be sharp so it may not give a consistent result.

    Brian.
    PLEASE - no friends requests or private emails, I simply don't have time to reply to them all.
    It's better to share your questions and answers on Edaboard so we can all benefit from each others experiences.



--[[ ]]--