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  3. New part/module to test

New part/module to test

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  • dbemowskD Offline
    dbemowskD Offline
    dbemowsk
    wrote on last edited by
    #1

    So I found this speaker module that I salvaged from an old Dell computer that looks a bit interesting. It appears to take a 5V power input and an audio signal and runs the small speaker with a built in amplifier. The diameter of the speaker is about 31mm and the whole module with the tab is about 44.45mm. The number on the chip is 4871 and appears to be a national semiconductor chip. When I looked that number up for NS, The only thing I found was an LM4871 which I am assuming is the chip as it is a 3W audio power amplifier.
    0_1526485986990_ad326749-ceb5-43d1-bba8-9920d3648d8e-image.png
    0_1526486015009_f81d754f-fc48-4b48-a450-402415d94370-image.png
    0_1526486029520_24e0d4f8-2a4a-407d-b903-a48a4955c42f-image.png

    Seems like it would be a good little module to use for some kind of audio alert/alarm for a project.

    It has 4 wires to it with 4 connections labeled on the board. There are the obvious P5V_IN, GND and AUD MONO. Which I assume are 5 volt power, ground and mono audio in respectively. I am not sure what SPK DET would be though. Does anyone have any ideas?

    Vera Plus running UI7 with MySensors, Sonoffs and 1-Wire devices
    Visit my website for more Bits, Bytes and Ramblings from me: http://dan.bemowski.info/

    mfalkviddM 1 Reply Last reply
    1
    • dbemowskD dbemowsk

      So I found this speaker module that I salvaged from an old Dell computer that looks a bit interesting. It appears to take a 5V power input and an audio signal and runs the small speaker with a built in amplifier. The diameter of the speaker is about 31mm and the whole module with the tab is about 44.45mm. The number on the chip is 4871 and appears to be a national semiconductor chip. When I looked that number up for NS, The only thing I found was an LM4871 which I am assuming is the chip as it is a 3W audio power amplifier.
      0_1526485986990_ad326749-ceb5-43d1-bba8-9920d3648d8e-image.png
      0_1526486015009_f81d754f-fc48-4b48-a450-402415d94370-image.png
      0_1526486029520_24e0d4f8-2a4a-407d-b903-a48a4955c42f-image.png

      Seems like it would be a good little module to use for some kind of audio alert/alarm for a project.

      It has 4 wires to it with 4 connections labeled on the board. There are the obvious P5V_IN, GND and AUD MONO. Which I assume are 5 volt power, ground and mono audio in respectively. I am not sure what SPK DET would be though. Does anyone have any ideas?

      mfalkviddM Offline
      mfalkviddM Offline
      mfalkvidd
      Mod
      wrote on last edited by mfalkvidd
      #2

      @dbemowsk

      I’m pretty sure the SPK DET lead allows the computer to know if there’s a speaker in place; my VOM shows it tied to ground.

      According to https://www.contrapositivediary.com/?p=1758

      dbemowskD 1 Reply Last reply
      0
      • mfalkviddM mfalkvidd

        @dbemowsk

        I’m pretty sure the SPK DET lead allows the computer to know if there’s a speaker in place; my VOM shows it tied to ground.

        According to https://www.contrapositivediary.com/?p=1758

        dbemowskD Offline
        dbemowskD Offline
        dbemowsk
        wrote on last edited by
        #3

        @mfalkvidd Great info. Thanks.

        Vera Plus running UI7 with MySensors, Sonoffs and 1-Wire devices
        Visit my website for more Bits, Bytes and Ramblings from me: http://dan.bemowski.info/

        1 Reply Last reply
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        • Nca78N Offline
          Nca78N Offline
          Nca78
          Hardware Contributor
          wrote on last edited by
          #4

          Interesting, they run from 2V, need only a few external component and and they cost peanuts on AliExpress, I'm buying 10 right now for testing with the speakers salvaged from my children toys.

          dbemowskD 1 Reply Last reply
          0
          • Nca78N Nca78

            Interesting, they run from 2V, need only a few external component and and they cost peanuts on AliExpress, I'm buying 10 right now for testing with the speakers salvaged from my children toys.

            dbemowskD Offline
            dbemowskD Offline
            dbemowsk
            wrote on last edited by dbemowsk
            #5

            @nca78 i assume you are talking about the amp chip. I think they are similar to the LM386. Sounds like they have a lower input voltage range.

            Vera Plus running UI7 with MySensors, Sonoffs and 1-Wire devices
            Visit my website for more Bits, Bytes and Ramblings from me: http://dan.bemowski.info/

            Nca78N 1 Reply Last reply
            0
            • dbemowskD dbemowsk

              @nca78 i assume you are talking about the amp chip. I think they are similar to the LM386. Sounds like they have a lower input voltage range.

              Nca78N Offline
              Nca78N Offline
              Nca78
              Hardware Contributor
              wrote on last edited by
              #6

              @dbemowsk said in New part/module to test:

              @nca78 i assume you are talking about the amp chip.

              Yes of course. I don't thing they are many speakers+PCB available on the market, maybe in the US but not here at least :)
              It looks pretty simple to use so it's not a problem to go with the chip.

              sundberg84S 1 Reply Last reply
              0
              • Nca78N Nca78

                @dbemowsk said in New part/module to test:

                @nca78 i assume you are talking about the amp chip.

                Yes of course. I don't thing they are many speakers+PCB available on the market, maybe in the US but not here at least :)
                It looks pretty simple to use so it's not a problem to go with the chip.

                sundberg84S Offline
                sundberg84S Offline
                sundberg84
                Hardware Contributor
                wrote on last edited by
                #7

                @nca78 said in New part/module to test:

                It looks pretty simple to use

                Getting sound out of an amplifier is pretty easy... but to get a good sound and filter all noise is harder, especially if you are going to use this near any RF signals or power supply. But you probably know this already...

                Controller: Proxmox VM - Home Assistant
                MySensors GW: Arduino Uno - W5100 Ethernet, Gw Shield Nrf24l01+ 2,4Ghz
                MySensors GW: Arduino Uno - Gw Shield RFM69, 433mhz
                RFLink GW - Arduino Mega + RFLink Shield, 433mhz

                Nca78N dbemowskD 2 Replies Last reply
                1
                • sundberg84S sundberg84

                  @nca78 said in New part/module to test:

                  It looks pretty simple to use

                  Getting sound out of an amplifier is pretty easy... but to get a good sound and filter all noise is harder, especially if you are going to use this near any RF signals or power supply. But you probably know this already...

                  Nca78N Offline
                  Nca78N Offline
                  Nca78
                  Hardware Contributor
                  wrote on last edited by
                  #8

                  @sundberg84 said in New part/module to test:

                  @nca78 said in New part/module to test:

                  It looks pretty simple to use

                  Getting sound out of an amplifier is pretty easy... but to get a good sound and filter all noise is harder, especially if you are going to use this near any RF signals or power supply. But you probably know this already...

                  I never did anything related to audio, it's not in my plans yet, but I'm looking for (it seems) something similar to what @dbemowsk says: make a loud noise/audible alarm and with only a handfull of parts. For that no need to worry too much about noise or distortion, I'm not planning to use it for music.

                  sundberg84S 1 Reply Last reply
                  1
                  • Nca78N Nca78

                    @sundberg84 said in New part/module to test:

                    @nca78 said in New part/module to test:

                    It looks pretty simple to use

                    Getting sound out of an amplifier is pretty easy... but to get a good sound and filter all noise is harder, especially if you are going to use this near any RF signals or power supply. But you probably know this already...

                    I never did anything related to audio, it's not in my plans yet, but I'm looking for (it seems) something similar to what @dbemowsk says: make a loud noise/audible alarm and with only a handfull of parts. For that no need to worry too much about noise or distortion, I'm not planning to use it for music.

                    sundberg84S Offline
                    sundberg84S Offline
                    sundberg84
                    Hardware Contributor
                    wrote on last edited by sundberg84
                    #9

                    @nca78 - sounds like a cool project. You will be able to amplify a analog signal using these chip like x100 (the more you amplify the more noice-killers you need) but even this will not be enough to make it very loud. Now, I dont know how "loud" you will need the alarm to be but most likely you need a more powerful amplifier for a household-alarm type of dB.

                    Controller: Proxmox VM - Home Assistant
                    MySensors GW: Arduino Uno - W5100 Ethernet, Gw Shield Nrf24l01+ 2,4Ghz
                    MySensors GW: Arduino Uno - Gw Shield RFM69, 433mhz
                    RFLink GW - Arduino Mega + RFLink Shield, 433mhz

                    Nca78N 1 Reply Last reply
                    0
                    • sundberg84S sundberg84

                      @nca78 - sounds like a cool project. You will be able to amplify a analog signal using these chip like x100 (the more you amplify the more noice-killers you need) but even this will not be enough to make it very loud. Now, I dont know how "loud" you will need the alarm to be but most likely you need a more powerful amplifier for a household-alarm type of dB.

                      Nca78N Offline
                      Nca78N Offline
                      Nca78
                      Hardware Contributor
                      wrote on last edited by
                      #10

                      @sundberg84 said in New part/module to test:

                      @nca78 - sounds like a cool project. You will be able to amplify a analog signal using these chips from a couple of mV to like x100 (the more you amplify the more noice-killers you need) but even this will not be enough to make it very loud. Now, I dont know how "loud" you will need the alarm to be but most likely you need a more powerful amplifier for a household-alarm type of dB.

                      Haha no, it's not for a home alarm but as an alarm for a sensor, possibly battery powered. Just need to be loud enough to be heard, but no need to pierce anyone's ear drums :D

                      sundberg84S 1 Reply Last reply
                      1
                      • Nca78N Nca78

                        @sundberg84 said in New part/module to test:

                        @nca78 - sounds like a cool project. You will be able to amplify a analog signal using these chips from a couple of mV to like x100 (the more you amplify the more noice-killers you need) but even this will not be enough to make it very loud. Now, I dont know how "loud" you will need the alarm to be but most likely you need a more powerful amplifier for a household-alarm type of dB.

                        Haha no, it's not for a home alarm but as an alarm for a sensor, possibly battery powered. Just need to be loud enough to be heard, but no need to pierce anyone's ear drums :D

                        sundberg84S Offline
                        sundberg84S Offline
                        sundberg84
                        Hardware Contributor
                        wrote on last edited by
                        #11

                        @nca78 Ahhh :D - the I think you will do just fine ;)

                        Controller: Proxmox VM - Home Assistant
                        MySensors GW: Arduino Uno - W5100 Ethernet, Gw Shield Nrf24l01+ 2,4Ghz
                        MySensors GW: Arduino Uno - Gw Shield RFM69, 433mhz
                        RFLink GW - Arduino Mega + RFLink Shield, 433mhz

                        1 Reply Last reply
                        1
                        • sundberg84S sundberg84

                          @nca78 said in New part/module to test:

                          It looks pretty simple to use

                          Getting sound out of an amplifier is pretty easy... but to get a good sound and filter all noise is harder, especially if you are going to use this near any RF signals or power supply. But you probably know this already...

                          dbemowskD Offline
                          dbemowskD Offline
                          dbemowsk
                          wrote on last edited by
                          #12

                          @sundberg84 not looking to do hi-fi sound, mainly to amplify an alarm or something simple.

                          Vera Plus running UI7 with MySensors, Sonoffs and 1-Wire devices
                          Visit my website for more Bits, Bytes and Ramblings from me: http://dan.bemowski.info/

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