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Thread: Compiled Pickup Data (Various Brands)

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    Compiled Pickup Data (Various Brands)

    So I've been scraping and arranging data here and there (many of you will recognize some of this info from somewhere) and decided to put it into a spreadsheet that anyone can use.

    Because I'm not really an experienced pickup maker, I thought it best to allow some smarter characters to make edits and - hopefully - contribute some of their own data to the spreadsheet.

    To make edits, simply make a comment here in this thread, then ask permission to edit on the Google sheet. That way I can confirm you're a trustworthy editor. If you see some stuff with conflicting info to what you have, please make a note rather than erasing it entirely - just so I can try to do a bit of research to corroborate before going with it.


    Anyway, here's the link (Google Docs).

    Let me know what you think, I'd be happy to know if anyone finds it helpful - and very grateful for contributions!


    e: I have a lot more data to add for other brands, but it's a struggle to organize it all - I never have the same sets of data for each brand, so it's hard to establish a standard format.

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    Last edited by jtb; 01-06-2020 at 02:20 AM.

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    Great idea jtb, brings to mind a very long ago idea around here called pickupedia.info which was a wiki page that could be edited by participants. Unfortunately it came to an end after a couple of years without much participation.

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    It is a cool idea. I found a one page list similar to yours and they had gauss of the magnets info also.

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    Some additional info/data:

    My original 1959 Strat PUs measure DCR: 5.9k/6.0k/6.0k, L: 2.44H/2.52H/2.50H, B: 950G - 1200G (indicating fully charged A5, no signs of aging!), magnetic polarity: North up.

    The '66 to '68 Fender Strat PUs I analyzed were wax - not lacquer - potted.


    In the context of our PAF magnet reengineering project we had around 20 dated Gibson magnets (taken from P-90s and PAFs, covering production years from 1954 to around 1967) lab analyzed. The survey also included some newer (US) production magnets of all relevant grades for reference purposes.

    The results were surprizing: All long magnets dating between 1954 and 1960 (around a dozen in total) were neither A2 nor A3 nor A5. While there was a little variance in chemical composition and magnet data (demagnetization curves), all these magnets could be positively identified as a (well documented traditional) variant of A4 (somewhat different from today's US A4). Particularly other standard grades could be excluded.

    Also some A4 in short magnets in the early 60s, but now A2 and A5 as well.

    These results were also published in the German G&B magazine (issue 12/18).

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    Last edited by Helmholtz; 01-05-2020 at 08:41 PM.
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    Nice Chart.
    Bobbin dimensions would be a nice addition, for those trying to make a vintage pickup from scratch!
    T

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    Quote Originally Posted by David King View Post
    Great idea jtb, brings to mind a very long ago idea around here called pickupedia.info which was a wiki page that could be edited by participants. Unfortunately it came to an end after a couple of years without much participation.
    I'm actually really frustrated with the lack of data online - I'm new to pickup winding, I'm mainly a luthier and I just got into it because I started designing an automatic pickup winding machine...I imagine people/companies are kind of cagey about their trade secrets though. Maybe I can find the original author on the wayback machine and see if he'll be willing to dump his data in this sheet too.



    Quote Originally Posted by glaze View Post
    It is a cool idea. I found a one page list similar to yours and they had gauss of the magnets info also.
    Any links or data you can provide would be greatly appreciated - I'd like to make this a community resource.


    Quote Originally Posted by Helmholtz View Post
    Some additional info/data:

    My original 1959 Strat PUs measure DCR: 5.9k/6.0k/6.0k, L: 2.44H/2.52H/2.50H, B: 950G - 1200G (indicating fully charged A5, no signs of aging!), magnetic polarity: North up.

    The '66 to '68 Fender Strat PUs I analyzed were wax - not lacquer - potted.


    In the context of our PAF magnet reengineering project we had around 20 dated Gibson magnets (taken from P-90s and PAFs, covering production years from 1954 to around 1967) lab analyzed. The survey also included some newer (US) production magnets of all relevant grades for reference purposes.

    The results were surprizing: All long magnets dating between 1954 and 1960 (around a dozen in total) were neither A2 nor A3 nor A5. While there was a little variance in chemical composition and magnet data (demagnetization curves), all these magnets could be positively identified as a (well documented traditional) variant of A4 (somewhat different from today's US A4). Particularly other standard grades could be excluded.

    Also some A4 in short magnets in the early 60s, but now A2 and A5 as well.

    These results were also published in the German G&B magazine (issue 12/18).
    If you'd be willing to make a couple edits to the chart, I'd be very grateful (and I'm sure noobs of the future will be too). I'm kind of annoyed that I was only able to find average per coil resistance data for the Fender guitars. That '59 Strat's resistance average is correct though, when taking an average of your numbers - so that's nice to have a little assurance with these numbers. They're dredged from the depths of the internet (and direct from manufacturers).

    I don't want to annoy you, but I have a ton of questions about pickups and you seem like a one-stop source for answers....can I message them to you?





    Quote Originally Posted by big_teee View Post
    Nice Chart.
    Bobbin dimensions would be a nice addition, for those trying to make a vintage pickup from scratch!
    T
    I can do a little research next weekend and see if I can find some numbers floating around - I was hoping some of you characters would want to make some edits since I'm sure all the data ever needed is stored collectively in this forums members

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    Quote Originally Posted by David King View Post
    Great idea jtb, brings to mind a very long ago idea around here called pickupedia.info which was a wiki page that could be edited by participants. Unfortunately it came to an end after a couple of years without much participation.
    Does this look familiar: https://web.archive.org/web/20110930...Specifications ?

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    That's familiar looking. I can't remember where the data came from or vouch for it's accuracy but don't have any reason to doubt it either. Unfortunately one of our core members here, jonson, passed away in 2015 or so and took a lifetime's worth of data with him. He'd offered it up to me and I hadn't realized the gravity of his situation at the time and hadn't acted on the offer. Spence might know more but he hasn't come around in quite a while.

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    I have some data on the B/H forum.
    https://music-electronics-forum.com/...0&d=1432942674
    https://music-electronics-forum.com/...4&d=1368391635
    http://www.jdguitarworks.com/coil/coil.html
    I can also calculate custom pickup data with bobbin core dimensions, upon request.
    GL,
    T

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    Quote Originally Posted by big_teee View Post
    I have some data on the B/H forum.
    https://music-electronics-forum.com/...0&d=1432942674
    https://music-electronics-forum.com/...4&d=1368391635
    http://www.jdguitarworks.com/coil/coil.html
    I can also calculate custom pickup data with bobbin core dimensions, upon request.
    GL,
    T
    Hi T
    Happy new year and hope all is well. The first link is dead, I just thought i'd mention it.
    Cheers
    Andrew

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    It works here, it is a xls spreadsheet.

    T
    Attached Files Attached Files

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    Last edited by big_teee; 01-06-2020 at 11:16 AM.


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    If you'd be willing to make a couple edits to the chart, I'd be very grateful (and I'm sure noobs of the future will be too).
    I think editing should be done by one person only.


    I'm kind of annoyed that I was only able to find average per coil resistance data for the Fender guitars. That '59 Strat's resistance average is correct though, when taking an average of your numbers
    But bear in mind that a temperature difference of 10C changes the DCR by 4%, so the same PU might read 5.76k or 6.0k depending on wire temperature (handling).
    Also measuring PU DCR without disconnecting the vol pot will give too low readings by 0.1k to 0.2k.

    Generally the influence of the DCR on the PU's frequency response is very small. Inductance is much more important.


    I don't want to annoy you, but I have a ton of questions about pickups and you seem like a one-stop source for answers....can I message them to you?
    I much prefer to answer your technical questions here on the forum, so that others can participate and maybe benefit.



    The Fender Strat PU part of your chart looks identical to this list:
    pudata.pdf

    IIRC this is based on measurements performed by Seymour Duncan.
    But note that magnet polarity should be north for 1958/1959.


    There is a huge PU data collection here (maintained by MEF member Antigua):
    http://guitarnuts2.proboards.com/thr...es-discussions

    http://echoesofmars.com/pickup_data/...ot~(~)~filter~')

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    Last edited by Helmholtz; 01-06-2020 at 10:39 PM.
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    Thanks Terry
    That link didn't want to download directly for some reason but I used J downloader and it came through fine.
    Cheers
    Andrew

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    Like helmholtz noted- holding a pickup in your hand for a little while will change the resistance. One mistake I saw right off the bat is jazzmater resistance is actually around 8 to 8.2K even though the turn count is similar to a strat- different coil shape. Resistance is futile.

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    Alright so there's a lot of stuff I have to start cataloguing in this thread - which is perfect! Thanks!

    Not to mention I found a few more spreadsheet pages on my computer with more data, and then links to manufacturer data repositories...this might take a while..

    But any ideas or other stuff to contribute will still be appreciated - I'll post again once I've got it all sorted out for a second review.

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    The document is titled "Pickup Specifications", technically these are measurements. The specification is what the manufacturer intended, but what is in hand might (probably) vary from the specification. For example, the document says a particular Stratocaster pickup in 1962 had 8220 turns, but it's very not likely that Fender spec'd that turn count for that year.

    Also I see them referred to as "hand wound", that's modern parlance in the market place, but technically they're hand guided and/or hand tensioned. I think only a few pickups in existence were actually wound by hand, one turn at a time.

    For the purpose of recreating pickups, it would be arduous to collect turn counts of pickups, because it requires dismantling them and it's a lot of work, but with a $100 LCR meter you can record inductances without having to take them apart at all, and from that you would only have to determine how many turns it takes to arrive at that inductance, and upon doing so, you would have created a pickup that electronically performs like the target pickup. The turn count alone can be misleading if other factors affecting inductance aren't account for. For example, Wilde Pickups is offering an AlNiCo version of their microcoil, but it appears that they retained the same turn count, but because the AlNiCo has a lower permeability than the steel screws of the original, the inductance is a lot lower and it sounds a lot brighter, and that might not have been the intended outcome.

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    Last edited by Antigua; 01-07-2020 at 03:30 AM.

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    Quote Originally Posted by Antigua View Post
    For the purpose of recreating pickups, it would be arduous to collect turn counts of pickups, because it requires dismantling them and it's a lot of work, but with a $100 LCR meter you can record inductances without having to take them apart at all, and from that you would only have to determine how many turns it takes to arrive at that inductance, and upon doing so, you would have created a pickup that electronically performs like the target pickup.
    I'm pretty new to reverse engineering the things - is there a guide or calculator that can help determine turns from inductance measurements? I found a bunch of resistance ratings per meter for various wires, but it didn't help me too much.

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    Quote Originally Posted by jtb View Post
    I'm pretty new to reverse engineering the things - is there a guide or calculator that can help determine turns from inductance measurements? I found a bunch of resistance ratings per meter for various wires, but it didn't help me too much.
    I'm seeing a DE-5000 on Amazon for only $80 right now https://www.amazon.com/Labs-DE-5000-...qid=1578428155 , the cheapest Ive ever seen it go for. When set to inductance series mode (Ls) at 100Hz, it gives good inductance values for guitar pickups, even ones with a lot of steel parts and excessive eddy currents. When set to capacitance parallel (Cp) at 100kHz it gives very good capacitance values as well. I've measured a lot of capacitances from inductance and resonant peak measurements, and found that the DE-5000's measurements are almost always right on the money. The DE-5000 also measured DCR as it's final mode, which unlike the Extech meter, saves you from having to use a separate ohm meter to get that value.

    Note that pickups with a foot of shielded hookup wire will read an extra 40pF to 80pF capacitance due to the presence of shielding, you would have to disconnect the hookup wire in order to get a true capacitance measure. The capacitance is not a highly important figure, so it might not be worth the trouble of removing it. Alternatively you can measure the length of the hookup cable and just make note of it so that it can be accounted for along with the measured capacitance. Fender style pickups with distinct lead wires add no capacitance (<1pF) so long as the wires are not touching together. The inductance is much, much larger than the capacitance, relatively, but if you're trying to recreate a pickup, and the target happens to have a very high or very low capacitance, you might get better accuracy by taking it into account. For example, most Strat pickups measure around 100pF, but you might be tasked with recreating one that happens to measure over 200pF, or you would want to make sure yours dont read over 200pF if the target is closer to 100pF.

    As for determining the turns, there's no good way to do that either with DCR or inductance, because with several thousand turns on a coil, there is a lot of room for drift and non-ideal factors. The only way to do get the turn count is to unwind and rewind it, counting how many turns it completes when it reaches the end of the wire. I know some people measure DC resistance as they're winding the pickup, they'll stop and check the DC resistance, and then keep winding until they reach a certain mark, I'd think the same could be done with inductance, except that any steel pole pieces would have to be present in the bobbin. An inductance measurement of a coil without its steel slugs or screws would be invalid. The inductance metric will be more accurate than the DC resistance, because the inductance doesn't care what the wire gauge is, where as the DC resistance is be heavily dependent on it.

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    help determine turns from inductance measurements
    It may help to know that inductance increases with the number of turns squared. So 10% more turns roughly produce 20% higher inductance, everything else being unchanged.

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    Quote Originally Posted by jtb View Post
    Alright so there's a lot of stuff I have to start cataloguing in this thread - which is perfect! Thanks!

    Not to mention I found a few more spreadsheet pages on my computer with more data, and then links to manufacturer data repositories...this might take a while..

    But any ideas or other stuff to contribute will still be appreciated - I'll post again once I've got it all sorted out for a second review.
    jtb, I would continue on with you data gathering and spreadsheet, and not get sidetracked with the LCR data.
    GL,
    T

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    Quote Originally Posted by big_teee View Post
    jtb, I would continue on with you data gathering and spreadsheet, and not get sidetracked with the LCR data.
    GL,
    T
    Don't worry, I still intend on that - I figure I'll just get it all in place and then decide what's helpful and what's not. The info I've gotten about inductance/winds is pretty much where I was at before: wishing I had some formal electrical engineering training. Maybe someone can just tell me if this thinking is correct:

    [pickup inductance] / [wire gauge & material resistance per meter] = [length of wire on the bobbin]

    which would then allow the number of winds to be calculated with a formula to account for the increasing distance per wind as the coil grows?

    If there's a formula for all this, I'd like to make a nice little calculator script for it.

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    [pickup inductance] / [wire gauge & material resistance per meter] = [length of wire on the bobbin]
    No, inductance depends on all coil dimensions as well as core type and nearby conductive or ferromagnetic parts - and of course on the number of turns squared.

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    Quote Originally Posted by jtb View Post
    Don't worry, I still intend on that - I figure I'll just get it all in place and then decide what's helpful and what's not. The info I've gotten about inductance/winds is pretty much where I was at before: wishing I had some formal electrical engineering training. Maybe someone can just tell me if this thinking is correct:

    [pickup inductance] / [wire gauge & material resistance per meter] = [length of wire on the bobbin]

    which would then allow the number of winds to be calculated with a formula to account for the increasing distance per wind as the coil grows?

    If there's a formula for all this, I'd like to make a nice little calculator script for it.
    There's not really any way to calculate turn counts to a precision that is better than +/- 100. If you wanted a high precision data set, you would have to unwind a lot of pickup and count the turns. Ideally that would be great, because suppose you want to clone a pickup, even if you could match the inductance, duplicating the turn count just seems more impressive. But how can you get all those turn counts? The only way I know of, is the manufacturer disclosing the info, which most will not, or dismantling a lot of pickups. That would cost a lot of time and money. If you repair pickups, you could gather than info as you repair pickups one at a time, and it seems that this is how Seymour Duncan acquired data about various Stratocaster pickups in the Fender portion of your database. But if you wanted to grow the database more quickly, you would have to buy an example of each, since you probably can't dismantle a pickup you don't own.

    If instead you don't plan to gather the data directly, but just gather from outside sources, you ought to put where the data came from. For example, the PRS data appears to have come from a spec sheet that dates back to 1995 http://u.cubeupload.com/Border_Collie/IMG0966.jpg , noting the original source is important for establishing veracity, and or how up to date it is.

    Another resource that would be helpful, is as you mentioned, it's difficult to correlate either inductance or DC resistance with turn counts. On the bright side, there is only a small handful of pickup form factors that are very common, Strat and Tele bobbins with A2 or A5 pole pieces, PAF type with screws and slugs, P-90's, Filter'trons and some base guitar pickups. After that they become less common. You could take a generic Strat bobbin with ALNiCo 5 pole pieces, wind on 500 turns of 42 AWG, measure the DC resistance and the inductance, and then write it down, add another 500 turns, measure it again, and in the end create a table that allows you to guess approximately how many turns on 42AWG on an AlNiCo 5 Strat bobbin it takes to reach a target DC resistance or inductance. Then if you know the target inductance or DC resistance, you can refer to that table to approximate how many turns it would take to get to that target measurement, cutting down on the amount of trial and error.

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    Quote Originally Posted by Helmholtz View Post
    No, inductance depends on all coil dimensions as well as core type and nearby conductive or ferromagnetic parts - and of course on the number of turns squared.
    That was dumb of me not to be considering the whole :|

    Is there already a complete formula for this in existence? That's what I'm really looking for I think, it'd help me come up with some better questions at the very least. I'm gonna go google around a bit.



    Quote Originally Posted by Antigua View Post
    Another resource that would be helpful, is as you mentioned, it's difficult to correlate either inductance or DC resistance with turn counts. On the bright side, there is only a small handful of pickup form factors that are very common, Strat and Tele bobbins with A2 or A5 pole pieces, PAF type with screws and slugs, P-90's, Filter'trons and some base guitar pickups. After that they become less common. You could take a generic Strat bobbin with ALNiCo 5 pole pieces, wind on 500 turns of 42 AWG, measure the DC resistance and the inductance, and then write it down, add another 500 turns, measure it again, and in the end create a table that allows you to guess approximately how many turns on 42AWG on an AlNiCo 5 Strat bobbin it takes to reach a target DC resistance or inductance. Then if you know the target inductance or DC resistance, you can refer to that table to approximate how many turns it would take to get to that target measurement, cutting down on the amount of trial and error.
    I was hoping workable data would already be in existence with some known material qualities, like the magnet types/strengths, wire gauges and metals, insulation types, etc. I wrote this down about 6 months ago in a spreadsheet, but I never included any context for it so I'm not sure how I intended to use it - I know I wanted it to make a calculator though:



    I've got a migraine now so I can't do much thinking anymore tonight, but I'll just paste something here and maybe you can tell me if you think it'd be accurate enough to make comfortable inferences from: http://www.jdguitarworks.com/coil/coil.html

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    Is there already a complete formula for this in existence?
    I completely understand what you are looking for. But unfortunately there is no such comprehensive formula. There are just too many complex interdependencies between parts and dimensions.

    In his book "Physics of the Electric Guitar" Prof. Manfred Zollner presents a lengthy and complicated formula (depending on length, width, height and thickness of the coil as well as turns number squared) that allows to calculate the inductance of an isolated PU coil (without any metal parts) to good accuracy. But as soon as you add polepieces and/or other metal parts, the inductance changes considerably. E.g. the inductance for a Strat PU calculated from the formula increases by around 30% when inserting A5 poles. Other pole materials and pole dimensions have different effects. Even the pole charge may matters (a little).

    The formula only works if the final coil dimensions are known to good accuracy.

    Wire resistance has no influence on inductance.

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    Last edited by Helmholtz; 01-08-2020 at 08:16 PM.
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    Quote Originally Posted by Helmholtz View Post
    Wire resistance has no influence on inductance.
    Someone posted a picture of PRS's pickup data above and there's a column labeled "resistance", which shows 15k, 11k, 8.8k, etc for the coils.

    I'm just wondering why and when one would measure resistance or inductance, what each measurement's purpose is in pickup making. Sorry for this super noob question that's totally off-topic here, but this seems to have turned into my crash course in pickup deconstruction.

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    I'm just wondering why and when one would measure resistance or inductance, what each measurement's purpose is in pickup making.
    Resistance is just an unavoidable side effect of any conductor. The longer and thinner the wire the higher its resistance. But PUs would work just fine if resistance were zero.
    OTOH, inductance is an electromagnetic coil property that mainly determines a PU's frequency response together with the cable capacitance. Together they produce a resonant peak and determine the bandwidth.

    A PU's output increases with the turns number.

    So if you know inductance and the turns number, there is no need to care about resistance.

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    Last edited by Helmholtz; 01-09-2020 at 04:15 PM.
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    Quote Originally Posted by jtb View Post
    Someone posted a picture of PRS's pickup data above and there's a column labeled "resistance", which shows 15k, 11k, 8.8k, etc for the coils.

    I'm just wondering why and when one would measure resistance or inductance, what each measurement's purpose is in pickup making. Sorry for this super noob question that's totally off-topic here, but this seems to have turned into my crash course in pickup deconstruction.
    If you know the DC resistance and the wire gauge, you can rough guess the turn count based on the resistance per foot of 42AWG and a knowledge of how many feet of wire it takes to achieve so many turns, but for various reasons it would never be too accurate, because DC resistance changes with temperature, and wire can stretch, becoming thinner than its nominal thickness, as it's wound onto the bobbin, resulting in a higher DC resistance for a given number of turns.

    The inductance really tells you if you reached an objective or not. For example, if I have a Strat pickup that is 2.65 henries, and I want a copy of that pickup, the real test of whether the copy is precise is whether or not the duplicate is also 2.65 henries. It could have the same DC resistance, and even the same number of turns, but if its not 2.65 henries, the copy liable to sound a little different, because it will have a different resonant peak. If the turn count is the same, there are good odds that the inductance will also be very close, but the two values can still drift somewhat.

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    If you're mass producing a particular pickup and want consistency then measuring inductance is a quick way to check for defects in the wind. Say there is an internal short in the coil where insulation got rubbed off and a few hundred turns disappeared. You wouldn't see that necessarily with a DCR test but you might hear it and presumably an induction test will show it.

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    you really should see a few hundred turns missing with a DCR test especially if it open circuits!

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