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  • Active Strat pickups - all dead?

    Hi all,

    sorry for the huge post - here's a tech question regarding my stratocaster. I bought this guitar used a long while ago with active Seynour Duncan pickups. Beautiful sound and feel. When the thing failed, I took it to the shop. According to them, two of my pickups are dead (shorted out). They did mention that one of them was still working (neck or bridge, can't remember).

    Question 1: which pickups are they? Do they really just break for no good reason?





    The shop left me with desoldered pickups. I can solder, but I don't understand electronics. In the image, you can see the 'stellar' soldering job that was done by whoever fitted the instrument with these pickups.





    I wanted to know which pickup is good and started by desoldering everything and cleaning up as much as possible. You can see the crazy amount of solder I took out.



    Next, I soldered everything back together again, however, the wiring scheme I used was different from what was used before. Before, every leg of the 5-way switch and the pots were used. I referred to a wiring scheme I found here which is shown below. One leg of the capacitor broke off, but my understanding is that this only affects the sound somehow and is not a vital part for testing. No sound from any pickup.

    Click image for larger version

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    For further testing, I de-soldered again to test each pickup individually. The pups are still connected together at the batteries and ground, but the leads are separated - is this a good test setup? When I connect to the guitar out, the batteries get hot. Fresh batteries dropped 1V within a minute or less. No sound from tapping the pickups with a screwdriver.


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    Would be grateful for any input!

    Thanks,
    Stefan
    Last edited by stefangs; 08-07-2020, 08:54 AM.

  • #2
    What you have are a set of the original Livewire 18v strat pickups. It's pretty rare for them to die unexpectedly. The schematic is good and it does work. You can measure to see if you get a resistance reading for each pickup between the ground and white wire. You will need to set the multi-meter to 200K range and you will get a resistance reading around 200K.

    The first thing I notice is the pots look like EMG pots which are 25K and not the 100K specified for those pickups. The second is the wiring job was really poor and the grounds are a mess. The third thing I notice is there's no output wire going from the middle lug on the volume pot to the tip of the output jack. It's really easy to get the tip, ring, and sleeve mixed up on a stereo jack.

    I would start by removing the tone controls from the circuit by unsoldering them from the switch. Solder the grounds to back of the volume pot, solder the red wires together and connect to the battery jacks. Then solder the middle volume lug to the tip of the jack which is the longest of the prongs, the ground goes to the shortest lug in the center of the jack, the red wires go to the ring which is the second longest prong on the jack. If you can get things working with just the volume you can then try reattaching the tone controls. This is the phantom power box I designed for mine it will help you identify the prongs. The cable completes the circuit between the ring and sleeve.

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    Last edited by idsnowdog; 08-07-2020, 01:14 PM.

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    • #3
      Thanks for your detailed feedback - a couple of questions, if you please...

      1) Measuring between the white pickup wire and ground, I do not get a reading. My understanding is that this is normal, since I'd be probing at the outputs of an op amp rather than the coil. Is this not true?

      2) Unfortunately, your graphic does not include the 1/2/3 pinouts on the actual diagram, i.e. it does not tell me which pin is supposed to go from the batteries to the pickups. It looks more like a closed loop without a pickup. But I think this is explained in the wiring diagram above where the ring is supposed to go to the black (minus) batteries and hot/ground to the pickups. This makes sense, since a guitar (mono) cable then connects both the battery and signal end to ground, thereby engaging the battery - did I get this right?. I double, triple, and quadruple checked that I have tip, ring, and sleeve correct.

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      • #4
        Originally posted by stefangs View Post
        Thanks for your detailed feedback - a couple of questions, if you please...

        1) Measuring between the white pickup wire and ground, I do not get a reading. My understanding is that this is normal, since I'd be probing at the outputs of an op amp rather than the coil. Is this not true?

        2) Unfortunately, your graphic does not include the 1/2/3 pinouts on the actual diagram, i.e. it does not tell me which pin is supposed to go from the batteries to the pickups. It looks more like a closed loop without a pickup. But I think this is explained in the wiring diagram above where the ring is supposed to go to the black (minus) batteries and hot/ground to the pickups. This makes sense, since a guitar (mono) cable then connects both the battery and signal end to ground, thereby engaging the battery - did I get this right?. I double, triple, and quadruple checked that I have tip, ring, and sleeve correct.
        1)You can still measure the resistance of the coils with active pickups. Basically you have signal, common ground and voltage input. Both EMG's and Livewires have three conductors. The coils should read 200K. For example here are two pictures of a dual-mode EMG-89. One set of wires reads 65K while the other reads 120K. The 65K is the single coil mode while the 120K is the humbucker mode. If your pickups read 200K then they are still good.

        2)My diagram is for how to build a phantom power box. However, in the left bottom you have a picture of a stereo jack which will help you see what each prong looks like. SD's diagram does not do that and you can match the wires from the SD diagram with the photo of the actual jack.

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        Last edited by idsnowdog; 08-07-2020, 01:50 PM.

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        • #5
          I see what you mean - thanks for clarifying! I understand the graph now in relation to phantom power.

          In the meantime, I have disconnected all pickups again, so the power leads are not ganged to the battery. I found that the middle pickup has a short between power and ground.

          Don't know if I could find the resources around the site here to find the bad part in the PU. That may be worth a try.
           

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          • #6
            As Meatloaf said two out of three aint bad. Do you get any resistance reading for the middle white and ground? If not maybe the op amp fried?
            Last edited by idsnowdog; 08-07-2020, 03:29 PM.

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            • #7
              Originally posted by idsnowdog View Post
              As Meatloaf said two out of three aint bad. Do you get any resistance reading for the middle white and ground? If not maybe the op amp fried?
              Nope, no reading there :-(

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              • #8
                Originally posted by idsnowdog View Post
                1)You can still measure the resistance of the coils with active pickups. Basically you have signal, common ground and voltage input. Both EMG's and Livewires have three conductors. The coils should read 200K. For example here are two pictures of a dual-mode EMG-89. One set of wires reads 65K while the other reads 120K. The 65K is the single coil mode while the 120K is the humbucker mode. If your pickups read 200K then they are still good.
                Crazy amount of leads - what a monster pickup! After you put a few of those on your strat, I don't want to debug the pickguard ;-)

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                • #9
                  The middle pickup is epoxy potted so there's no way to tear it apart and repair it. I bought two Livewire singles on Reverb two weeks ago. They are hard to find and usually expensive. You can mix other actives with the Livewires and I had EMGs+Livewires in one guitar and Blackouts+EMGs in another and they didn't mix well due to output and tone differences. I would be interested to see how well the GFS Red Actives with three DIP switches sound compared to Livewires because they are cheap and easy to find. The three DIP switch settings may make up for some of the volume and tone mismatch between the two?

                  Last edited by idsnowdog; 08-08-2020, 05:03 AM.

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                  • #10
                    That's too bad they can't be taken apart. I don't feel like replacing the middle pickup, especially not if it's a hard to find item. I might as well sell the two working ones and replace all three with something else.

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                    • #11
                      Originally posted by stefangs View Post
                      That's too bad they can't be taken apart. I don't feel like replacing the middle pickup, especially not if it's a hard to find item. I might as well sell the two working ones and replace all three with something else.
                      Let me know what you want for the two.

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                      • #12
                        I have a 24 fret Jazz Bass with the active Duncans with the DIP switches. One of those are dead.

                        It always struck me as odd that epoxy encapsulated pickups would fail, but there must have been something in their manufacturing design that was a weak spot.


                        Sent from my iPhone using Tapatalk

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                        • #13
                          Originally posted by DavidRavenMoon View Post
                          I have a 24 fret Jazz Bass with the active Duncans with the DIP switches. One of those are dead.

                          It always struck me as odd that epoxy encapsulated pickups would fail, but there must have been something in their manufacturing design that was a weak spot.


                          Sent from my iPhone using Tapatalk
                          I agree - I can't think of a good reason to epoxy all that stuff. Sounds like planned obsolescence - anything with parts that can fail should be accessible. It doesn't necessarily have to be easy.

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                          • #14
                            Originally posted by stefangs View Post

                            I agree - I can't think of a good reason to epoxy all that stuff. Sounds like planned obsolescence - anything with parts that can fail should be accessible. It doesn't necessarily have to be easy.
                            The concept behind epoxy potted pickups is that they are supposed to be able to withstand high sound pressure levels without being microphonic. They are also supposed to be more durable and not susceptible to environmental damage but the downside is if anything internally shorts out they are dead and can't be repaired.

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                            • #15
                              So with the help of the folks over at gearslutz, I threw out the middle pickup and wired the rest in Telecaster fashion with a 5-way switch mod. That will keep me going for a while until I find a replacement for the pickups which will happen eventually. Thanks for helping me out here - greatly appreciate it!

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