Technics SAGX690 One Channel Cuts Out Intermittently

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  • เผยแพร่เมื่อ 21 ก.ย. 2024
  • A nice easy one for a change

ความคิดเห็น • 21

  • @tylerlloydboone
    @tylerlloydboone 2 วันที่ผ่านมา +7

    Technics made decent stuff. Newer subscriber here. Digging the channel. Keep it up

  • @mmichaelnowell1512
    @mmichaelnowell1512 วันที่ผ่านมา

    I had the SA-EX320 That was the best little receiver I ever had,it lasted 25 years, not one problem sold it last year for $125.00, guy contacted me! Said that little receiver works excellent!, have all of my panasonic vcrs & dvd player!

  • @AstrosElectronicsLab
    @AstrosElectronicsLab 2 วันที่ผ่านมา +5

    Love the technical "let's see if this fixes it", bash the top of it with your hand! 🤣I do that all the time. Lol, I know what you were doing (bad solder joints possibly, maybe a jolt will restore sound).

    • @monz7951
      @monz7951 วันที่ผ่านมา +1

      Lol yeah I love his method of no bs repairs, straight to the point and it works. I diagnosed and fixed an expensive bass amp two techs had already given up on the same way, crappy lead free solder joints

    • @12voltvids
      @12voltvids  วันที่ผ่านมา +2

      Every shop does this. Customers would be freaking out if they knew how their equipment was treated. Why do you think shops would not allow customers in the back and if they were hanging around wouldn't work on their stuff till they left. Even if we weren't busy we never started on something until the customer left. Otherwise they would be strolling into the back to watch.

  • @stereomann83
    @stereomann83 2 วันที่ผ่านมา

    I think that receiver is from the mid 90's i had a Cassette Deck TR 373 that had the same design. i think most of the receivers used a fan for cooling. luckily that was an easy repair that you could get at easily. too bad the whole bottom cover doesn't come off.

  • @simplerick3851
    @simplerick3851 วันที่ผ่านมา

    My technics also cuts out on one channel. Flipped it over and sure enough it has a removable panel... Now if I only knew what I was doing.. 😮

  • @markmarkofkane8167
    @markmarkofkane8167 2 วันที่ผ่านมา

    I like to guess before watching. Bad solder joint or transistor.
    I am fascinated by learning and watching.

  • @helpaholic
    @helpaholic วันที่ผ่านมา

    So in the end, it looks like you were soldering every other one or everyone, but you never did explain why or what it looks like when there’s something wrong with it in terms of the solder I couldn’t really tell

  • @jiml20
    @jiml20 วันที่ผ่านมา +1

    Why don't people ever remove the old solder and then apply new instead of reflowing sometimes you will get excessive solder and cause Bridges?

    • @12voltvids
      @12voltvids  วันที่ผ่านมา

      Only if you don't know how to solder. Experts don't bridge and if it happens its easy to remove.

    • @jiml20
      @jiml20 วันที่ผ่านมา

      @@12voltvids thanks for the reply I will assume the mixing of the old and new solder will not have any ill effects. Thanks for these informative videos

  • @staszeksowikowski9039
    @staszeksowikowski9039 2 วันที่ผ่านมา +1

    Hey, is the "class H" just a different name for what Technics used to call "New class A" or is it a different thing entirely? I got a SA-GX550 and that unit runs pretty hot, no wonder the connections go bad on the power amp boards on these.

    • @peterlarkin762
      @peterlarkin762 2 วันที่ผ่านมา

      New Class A was different to Class H. Class H is like class AB, but also has two power rails switching to the higher voltage rail when output demands more power. New class A is class AB, plus the bias intermittently turns the outputs on just as they begin to turn off as the wave swings. Same with Class AA, except there the bias varied via the feedback loop. Class AB amps can vary a LOT in terms of biasing and other circuitry, and can sound like Class A in terms of harmonics.
      P.S. if yours is running worryingly hot, open it up and make sure it's not caked in dust and tighten up any output devices attached to the heatsinks.

    • @staszeksowikowski9039
      @staszeksowikowski9039 วันที่ผ่านมา

      @@peterlarkin762 Thanks for the explaination. I have serviced my unit and replaced the thermal compound on the main heatsink as well as repaired my faulty fan drive. The inoperable fan was causing it to cut out the sound (protection). I think these units just run hot with the limited vents on top.

    • @12voltvids
      @12voltvids  วันที่ผ่านมา +1

      New class A is the same as sonys legato linear and Yamaha natural sound. Its a class ab amp that increases the bias at low levels to keep the outputs from going into cut off. So both the npn and pnp are kept biased hot. The bias lowers as the signal level increases. At about 9 watts the amplifier is working as a full class ab. Class h is a dual rail design. Low vilrage high current and higher voltage lower current reserve for quick transients that would cause clipping. By lower current I am referring to the capacitor reserve. Might use 70,000uf for the +- 50 volt rail and 6800uf for the +-80v rail because it is only switched in momentarily as needed and the majority of the current is from the low voltage rail.

  • @HearTbeat_999
    @HearTbeat_999 วันที่ผ่านมา +2

    The “L” is silent in the word solder ( “sodder”) … I’m just saying 😂

    • @gower1973
      @gower1973 วันที่ผ่านมา +1

      Only in America its silent the rest of Empire speaks the proper English

    • @12voltvids
      @12voltvids  วันที่ผ่านมา +1

      Thats an american thing. Thats ok you pronounce many words incorrectly.

  • @helpaholic
    @helpaholic วันที่ผ่านมา +1

    So he smokes in the garage with the equipment, but not in his house.

    • @12voltvids
      @12voltvids  วันที่ผ่านมา

      Did I say that? No, I said there is evidence of this unit being in a smoky environment. The fella actually bought it for 40.00 for his garage. The previous owner likely smoked.