TDGAUDIO NFC-83A ceiling speaker crossover repair(no output)

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • r2digital
    Member
    • Sep 2011
    • 39

    #1

    TDGAUDIO NFC-83A ceiling speaker crossover repair(no output)

    Hey guys, im trying to figure out why my ceiling speaker has no output from the woofer or tweeter. I cannot seem to get a resistance at the main input speaker terminals but i did measure resistance at the woofer and at the tweeter wires individually and everything seems to be OK. Ive done a little bit of troubleshooting on my own and when i was probing the negative terminal in combination with any component (PTC fuse, the capacitor, and any of the resistors) on the crossover i get no continuity what so ever. However, when i take the same model speaker but a fully working one and i probe the negative terminal in combination with any of the components listed above i get continuity. What section of the crossover would cause a no output condition? I've been toying with the fact that its the PTC resettable fuse but i am unsure if its used to only protect the tweeter or if its used to protect the entire design.



    Join Date: Aug 2010
    I checked all the resistors and the values are as follows

    25w2ΩJ=1.5
    25w2ΩJ=1.5
    10w2.2ΩJ=1.4
    10w2.2ΩJ=1.4
    10w2.7ΩJ=2.8

  • stj
    Great Sage 齊天大聖
    • Dec 2009
    • 30983
    • Albion

    #2
    Re: TDGAUDIO NFC-83A ceiling speaker crossover repair(no output)

    thats a stupid design, the vibration will fuck the soldering.
    check the joints on the back of the board.

    Comment

    • r2digital
      Member
      • Sep 2011
      • 39

      #3
      Re: TDGAUDIO NFC-83A ceiling speaker crossover repair(no output)

      I will touch up and reflow all the joints on the back of the PCB. Do the resistance values seem correct? When i check the resistance values of the same model of a working speaker the results are much closer to their rating.
      For example the
      25W2ohmJ=2.2ohms
      10W2.2ohmJ=2.3

      Should i be concerned the the different values on the non working speakers?

      Comment

      • r2digital
        Member
        • Sep 2011
        • 39

        #4
        Re: TDGAUDIO NFC-83A ceiling speaker crossover repair(no output)

        looks like some one already got to the PCB before me. Lots of deep scratches on the pcb. I think maybe one of them is deep enough to cut a trace to the negative post?


        free animated gif flag
        Last edited by r2digital; 07-31-2021, 01:00 PM.

        Comment

        • petehall347
          Badcaps Legend
          • Jan 2015
          • 4426
          • United Kingdom

          #5
          Re: TDGAUDIO NFC-83A ceiling speaker crossover repair(no output)

          the thermistor is there to protect the tweeter .

          Comment

          • r2digital
            Member
            • Sep 2011
            • 39

            #6
            Re: TDGAUDIO NFC-83A ceiling speaker crossover repair(no output)

            Does anyone what i should check if i have no output from the tweeter/midbass? Verified the tweeter and midbass work fine individually

            Comment

            • stj
              Great Sage 齊天大聖
              • Dec 2009
              • 30983
              • Albion

              #7
              Re: TDGAUDIO NFC-83A ceiling speaker crossover repair(no output)

              draw the circuit.
              it doesnt look like a crossover though - only one cap.

              Comment

              Related Topics

              Collapse

              • waigy
                Nikkai EAPA 450 car amplifier rear speaker output is a low level and distorts easily
                by waigy
                As the title.
                I think these used to be sold in maplins a lot of years ago, it is an antique, but it's just fine for my needs.
                It looks basic enough inside with large components so I could do a full recap pretty easily.
                Any suggestions on what component would cause the symptoms of low volume output on both left and right rear speaker outputs?
                If I turn up the rear gain level in the amp until the speakers start to distort it starts to distort quickly even though the speakers are still pretty quiet.
                I thought I had dodgy speakers as I just fitted new old stock 6x9s in...
                11-08-2024, 03:53 AM
              • FrancescoV
                Onkyo HT-R390 no sound output, video output ok
                by FrancescoV
                Good morning everyone,
                I'm trying to repair an onkyo ht-r390 that has no sound output, despite the volume being at maximum, the rest seems to work; the video output signal (coming from an hdmi input) is present, but the audio is absent. Similar situation if I send an audio signal from any input I have no output.

                The firmware reported is the following:
                M:1.00/11107BLP
                D:?.??/????????
                O:1.00/11107AL

                The DSP firmware given the question marks seems corrupt.

                On the BCHDM-0678 - 25140678 - QPWBCHDM0678A0 board the chip that usually seems...
                05-11-2025, 02:59 AM
              • Z2yzx
                Denon AVR S720W Main Speaker no output.
                by Z2yzx
                Hi everyone!

                Does anyone out there have any insight as to why my AVR will not output sound through main speakers or head phones?

                Here is the info:
                Unit powers up normal
                Relays click
                Zone 2 works fine 100% of the time.
                Main Zone sometimes works fine like .05% of the time.
                Sometimes I can plug headphones and hear scratching sound via the headphones. Once that happens I can unplug the headphones and the main speaker zone works fine.

                is there something I can inspect?

                I have somewhat moderate skills with electronics....
                12-19-2023, 01:34 PM
              • Califauna
                Help with boom box modification
                by Califauna
                Hi, this is more of a project help request than a troubleshooting question. I hope I can post it here.

                I have a W-King D8 Bluetooth boom box which I'd like to modify with some external speaker output jacks and some buttons to switch the internal speakers on and off.

                From factory the specs of the boom box are:

                -Power Input: DC 5V
                -Speaker Output Power: 2 x 25W ( confirmed by Youtube channel Hartdegen review as 12.5W RMS per channel)
                -Drivers:
                -2 x Woofer, 70mm, 10Ω, 70mm,15W
                -2 X Tweeter, 8Ω, 30mm,10W x 2
                -Frequency...
                12-04-2021, 01:53 PM
              • sam_sam_sam
                NTE Electronics “NTE5251K” Zener Diode 9.1V @ 50W Do-5.5% Want to build a 9.1 output from a 9.6 lipo4 battery pack
                by sam_sam_sam
                I have bought this Zener Diode for this project what size and wattage resistor value do I need to use to get near 50 watt output
                I bought this from an eBay seller but unfortunately they only had one

                I bought three from Vetco Electronics these are Sylvania ECG5185A 9.1@10w A to Stud what size and watt resistor do I need to use to get near 10 watt output
                I bought three of from them to also make battery packs with this output power limit in mind

                I want to use this battery pack and turn it into a 9.1 output battery pack output to eliminate using 9 volt battery...
                04-23-2025, 05:50 AM
              • Loading...
              • No more items.
              Working...