Onkyo Integra A755 Mark 2 Integrated Amplifier Repairs Part 1 (Ep. 185)

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  • เผยแพร่เมื่อ 6 ต.ค. 2024
  • In this first part I track down the cause of a dead channel in the phono stage

ความคิดเห็น • 24

  • @Reflectiveness
    @Reflectiveness ปีที่แล้ว +7

    I know next to nothing about electronics, but like watching a true professional do the kind of work I would if I could. Thanks for sharing your skills.

  • @chrisdado
    @chrisdado ปีที่แล้ว +3

    I have never seen a rash of failed film caps like that, very unusual. Good luck with the Marantz, thanks for sharing Trevor.

  • @kadosas
    @kadosas ปีที่แล้ว +2

    I am so glad you are doing this video! I have the excact same amp. How it wounded up here in Denmark I don't know.
    I have had it for a view years now and restored it back in the time. I didn't check those blue caps though, because, like you, I assumed they should be fine. I have checked them today, and they are not fine, so thank you for pointing that out.
    I use my Onkyo with a transformer 220/110 volts and that seems to work fine. I have 33V on the rails before clipping and 40 in idle.
    I am looking forward to the point where you have to determine the bias. I have 6mV on the to outer terminals where it says "Check". Sinus looks wonderful on the scope, no crossover distortion. I get a max wattage of 38.72 Watt. Hope this help a litlle. Looking forward to part II.

    • @TrevorsBench
      @TrevorsBench  ปีที่แล้ว

      Good to hear you found the video useful. Those caps should have never failed since the see very little voltage.
      Also, thanks for the info. I don't know what the idling current should be but now I have a idea

  • @steveoszman8746
    @steveoszman8746 ปีที่แล้ว +1

    Thank you, I had similar trouble with my receiver left channel phono. Couple cracked cold solders and a failing cap. Was so happy some part made of unobtainium hadn't failed. Have a great week.

  • @knifeswitch5973
    @knifeswitch5973 ปีที่แล้ว +2

    Never owned an Oinkyo 🐷 til recently. A8067 from late 80’s I believe. In the middle of going through it right now but initial power test and some early listening sessions raised my eyebrows. That machine is a beautiful example of an early A! Excited for the nest episode and thanks Trevor

  • @geirendre
    @geirendre ปีที่แล้ว +5

    I don't mind the "To be continued" ending of these videos.
    Looking forward to the "Previously on 'Trevor's bench'" in the next episode 😊

  • @SergZak2023
    @SergZak2023 ปีที่แล้ว +2

    Although I’ve heard of the Onkyo brand, I don’t remember seeing it commonly in stores here in SoCal…or maybe I just wasn’t paying attention because I was interested in so many others at the time. Let’s get to part two!

  • @psyclobe
    @psyclobe ปีที่แล้ว +1

    Very well done thanks for making it

  • @johnbravo7542
    @johnbravo7542 ปีที่แล้ว

    Learning something new,I have seen the black legs on some transistors,in circuit of an amp a guy gave me,ages ago,but haven't had the time to work on it.I didn't know that was a thing.
    Great work looking forward to next video.

  • @zx8401ztv
    @zx8401ztv ปีที่แล้ว +1

    i was surprised that one poly film capacitor was bad.
    You were just lucky to win the jack pot lol.
    Repairing things can send you mad.. ok madder :-D

  • @alexismethenitis
    @alexismethenitis ปีที่แล้ว

    Already tuned!

  • @chaber6419
    @chaber6419 ปีที่แล้ว

    Those Kemet R82s...Long legged DQ,CK,Z3 codes aren't available anymore? Neat Onkyo to work on. Interesting catch on those blue mylars. Thanks Trevor!

  • @wallyhandyman
    @wallyhandyman ปีที่แล้ว

    this amp reminds me of the old fisher amp nice amp.

  • @gregf9160
    @gregf9160 ปีที่แล้ว

    That must be a bad batch of caps. Quality Control sure fell on its arse, that day!

  • @joeyjustin6895
    @joeyjustin6895 ปีที่แล้ว

    35:52. YOU DO NEED A 250V CAP TO PASS AN AUDIO SIGNAL. BECAUSE THATS WHY SABSUI HAS AN AUDIO SIGNATURE. I ACTUALLY USE 600V CAPS. BUT. IF YOU USE A LOWER VOLTAGE CAP THE SOUBD GETS COLDER.

  • @CharlieParkour
    @CharlieParkour ปีที่แล้ว +1

    I had no idea Onkyo had such pretty looking heritage. Were these made in Japan?

    • @CharlieParkour
      @CharlieParkour ปีที่แล้ว +1

      Never mind! Got to the 5 minute mark

  • @johnsenchak1428
    @johnsenchak1428 ปีที่แล้ว

    It's a to-92 transistor If you increase the primary side volts by about 12 Volts AC RMS (122volts RMS) , you might get another 5 watts per channel on the output because I don't think the voltage would be much more on the secondary side. This is because of the transformers turns ratio and the amount of energy stored in the core material I would also think that if you increased the voltage to American line voltage , the power factor would be better and the power would go down due to the inductive load Why are you not doing signal injection on the actual phono board ? You should have done the signal path from the start ! replace the capacitor on each side !

  • @zopilotesky3014
    @zopilotesky3014 ปีที่แล้ว

    Yeah, cursed. I've been working on a Sony TC-350 R2R that is just that. Every time I fix a problem something else rears its ugly head and sends me back to my bench. I've determined that its not worth the time I'm putting into it so its now a parts unit. Cursed no more. 😇

  • @Poppinwheeeeellllllieeeeez
    @Poppinwheeeeellllllieeeeez ปีที่แล้ว +3

    STOP SENDING SHORT VIDEOS 😂

  • @robertdavis5714
    @robertdavis5714 ปีที่แล้ว

    Nice production Trevor, whenever I do not recognize something, then always a Japanese import. Early 1970's just too many defective electronic parts manufactured, 1976-1979 for me. Ill remember those Blue Hitachi Caps.

  • @paulb4661
    @paulb4661 ปีที่แล้ว +1

    VIDEO IS TOO LOOOOOOOONG !!! 🤷‍♂️

  • @wayneg296
    @wayneg296 ปีที่แล้ว

    👍👍😎✌️🤟