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Post by ChrisK on Jan 20, 2009 20:53:01 GMT -5
No, the inductor has the innate tendency to keep the same current flowing thru it in the same direction regardless of external current flow.
While it's a hydraulic analogy, it depends on the compressibility of the air or the elasticity of the bladder for the analogous "field".
In other words, as current flows thru it, the magnetic field increases until the core saturation point is reached, and then it appears as only its wire resistance. This is called "locked rotor current" in a motor, and is to be avoided if possible.
When the external current is removed (or reduced), the stored energy, to use the water analogy, squirts out in the same direction. In the case of a coil such as a relay coil or ignition coil, a theoretically infinite voltage is developed as this finite current tries to flow thru an infinitely large load resistance.
This is why DC relay coils have an anti-parallel clamp diode (so the solid-state relay driver doesn't "go to be with Jesus"), and why automobile ignition systems work.
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Post by ChrisK on Jan 19, 2009 2:13:37 GMT -5
Yeah, they're habit-forming. I drive nearby them every week.
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Post by ChrisK on Jan 19, 2009 2:01:45 GMT -5
...an octave lower....an octave larger...
Sorry, I was being too clever in a clue.
If the frequency range is an octave lower (divided by 2), then, for an equal response effect (albeit an octave lower), the caps double (times 2) in value.
Yep.
Yep.
[/quote]
No, this will be the brightest.
BTW, uF (10^-6 Farads) and not pF (10^-12 Farads)
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Post by ChrisK on Jan 19, 2009 1:54:17 GMT -5
Is this how it's wired?  If so, I think that there are some isolation safety issues. The bridge and pickup cases are connected to the output jack (and hence amp) ground. The 0.1 uF 400 VDC (?0.33 uF 400 VDC?) cap only isolates the volume pot shell from the ground nexus. If the Faraday cage is conductive, nothing is isolated from anything and the cap is just excess baggage.  |
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Post by ChrisK on Jan 19, 2009 1:38:22 GMT -5
Between my time in the service and college I worked in pneumatics and hydraulics, so I do see these things as well. This is good to know. Electrical current is water. Voltage is water pressure. Sometimes it's gravity. Sometimes it's (differential) water level. Resistance is pipes of varying diameter/length. Capacitance is a storage tank. Inductance is an accumulator (like the things that reduce the water hammer effect - sort of). Imagine a two port device that water flows thru. It's a small pipe (gee about as small/long as the inductor's internal resistance) with many small holes in it. It is surrounded by an elastic bladder that "blows up" as water leaks into it from the water pressure. When the water stops flowing thru it, the stored water is forced out in the same direction by the elastic bladder returning to its previous static state. This effect is the stored magnetic energy of an inductor. An inductor stores energy. A capacitor stores charge/water. Now, things really don't work that way, do they? Or do they? If you're doing something to some part of a circuit that is a two port linear network, the two ports comprise an API. It's like a USB connector (or a VGA connector, or a headphone connector). as long as you follow the rules of the interface, you can plug in anything. In Fun with switches, take 2, at the bottom you can see that three identical submodules are combined into a design. In block "D" there is a module that switches two things, "A" and "B". Note that I DIDN'T say two pickups or two coils. "A" and "B" could just as validly be two capacitors for four tone cap choices if the submodule was treated as a two port network and used with a tone pot (cap "A"/cap "B"/both in parallel/both in series). The up arrow is the "goesuppa" and the down arrow is the "goesdowna". They're not necessarily the output and ground, but they could be one or the other, or both. Now. the magenta central module has an identical blue module on either side of it, with each blue module being the "A" and "B" of the magenta module. In this case, the "A's" and B's" for the blue modules are the coils. The "goesuppa" and "goesdowna" of each blue submodule feed into the "A" and "B" of the central module. The "goesuppa" and "goesdowna" of the central module goes to the tone and volume structure (although each coil on the blue submodules, or each submodule, or both could just as easily have their own volume and/or tone controls as well. So we have a "left" A/B/parallel/series submodule for two coils and a "right" A/B/parallel/series submodule for two other coils, and a central A/B/parallel/series module for two submodules. This could be for two dual-coil humbuckers, or a dual-coil humbucker (Bridge) and two single coil pickups (Middle and Neck). Selecting only the left submodule, we get four unique coil combinations (left A/B/parallel/series). Selecting only the right submodule, we get four unique coil combinations (right A/B/parallel/series). The two other central module combinations (parallel and series) gives us 16 combinations in each for a total of 40 unique coil combinations. Proofing this from the perspective that 6 two position switches give 2^ 6 or 64 possible combinations, and disallowing the 12 redundant ones each from the central "A" and central "B" selection gives 64 - 24 = 40. I did this example specifically to show structured submodule-based design. In this case, we have an iterative subroutine that is calling itself (in a stack-based-processor sort of software analogy - can you "C" it?).  |
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Post by ChrisK on Jan 19, 2009 0:50:10 GMT -5
Yikes, the nitro only "breathes" in a prophylactic sort of way. Be sure to practice safe tone.  Fender Guitars the Lacquer Nitro Cellulose Lie - Fullerplast - Fenders ... All Fender Guitars are Poly, Nitro is applied over the poly base coat www.caraguitars.com/contact.asp |
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Post by ChrisK on Jan 18, 2009 16:28:00 GMT -5
Try this. It wasn't the switch, it was the wayward connection to the output jack.  Octavius sez that you might want to use a 0.1 uF and a 0.047 uF cap for 0.1 uF, 0.030 uF, and 0.047 uF tone choices. |
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Post by ChrisK on Jan 18, 2009 16:16:21 GMT -5
It's probably polyurethane, but wait until others chime in.
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Post by ChrisK on Jan 18, 2009 15:50:21 GMT -5
Yep. In theory, the ratio of the frequency ranges between the two instruments should be used to scale the treble bypass cap. If it's an octave lower, the cap should be an octave larger (Q.E.D.). The same metric could apply to the tone control cap(s) as well. Now, if you CAN find caps measured in octaves, please do let me know.... I got a guitar wiring book for Christmas that indicated that a "stronger" cap should be used. WTF |
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Post by ChrisK on Jan 18, 2009 13:49:56 GMT -5
Cyn,
Please take great pride in your efforts. In more ways than you might think, you get things.
Also, you are most tolerant in that you take my comments and criticism in stride. Your willingness in this is much appreciated, since many of my comments are directed at a much wider audience than just you and these designs.
I also am learning from this. Helping you helps me see how many folk view guitar wiring and things electrical. This teaches me how to better explain things.
Your last post caused me to realize that it's not really the use of schematics (a language that I've spoken since I was less than 10 years old) that enables a better view of the landscape, but the practice of submodule isolation.
Wiring view is based on grouping things by where they are located while schematic view is based on grouping things by what they do by function.
In my considered opinion, the overall wiring view is too cluttered when used too early. A good analogy is software; most is a main line thread that calls subroutines.
Your prior post about your DPDT and SP3T humbucker switching is a module. Leave that on a separate sheet of paper (gif, jpg) and call its TWO external connections Bridge Pickup Signal and Bridge Pickup Return. These two signals connect to another module comprised of the bridge volume and bridge tone circuits. The output of the combinations of these two modules (now the Bridge structure) is TWO signals; the Bridge Structure Signal and Bridge Pickup Return (the latter carries thru within the structure). Let's call them BSS and BPR.
Now, since this structure will be ground referenced when in parallel, and electrically "perched atop" the Middle and Neck structure when in series, we should represent them on the initial main view solely as BSS and BPR, (and NOT by drawing any of the submodule's components). For now, that is.
Then we would draw the Middle and Neck structure since that is predominantly taken from another design that does almost exactly what we wanted (except for the phasing rather than full coil flexibility within the bridge pickup). We would then erase the existing bridge pickup structure (pickup, phase switch, tone circuit, and volume control - I did all of these to emphasize the overall bridge structure) and replace it with the two signal names BSS and BPR.
Since we have the new bridge structure on a separate sheet of "paper", it is abstracted from our overall view for now.
Once we're confident of the modified overall view (sans the bridge structure), where wiring view is fine to use since we're not trying to understand and modify it since we already "trust" it, we then can drop in the new bridge structure, connecting it only by its API (Abstraction Point Interface - I made this up just now, but it's most applicable), which is BSS and BPR.
We then have a complete view that is free of legacy influence.
This is how I teach young electrical design engineers to do schematic layout. First decide what existing design references you want to reuse, second, develop the new modules, and third, fold all into the new "omelet".
We actually capture all new modules into library objects. In many ways new printed circuit designs for new products makes use of these modules which have proven interfaces, SixSigma scores, agency approvals, accuracy, and testability inherent.
As one builds the library of modules, things become more and more like plumbing.
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Post by ChrisK on Jan 18, 2009 0:30:41 GMT -5
No, from the perspective of the guitar being a two-terminal device (signal output and ground), ground is a fine descriptor since this point is the ground potential and return point for the guitar signal.
My point is that the "ground-ness" of wires usually connected to signal ground leads most to assume that these are (always) ground wires. They are not.
Ground is a circuit node, it is not a component node.
How you look at something determines how you see it.
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Post by ChrisK on Jan 17, 2009 23:56:28 GMT -5
These screws are likely metric. If you can't find them at a local guitar store, try an auto parts store or even Lowes or The Home Depot. You can also try www.mcmaster.com as they seem to have stuff galore. |
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Post by ChrisK on Jan 17, 2009 23:40:32 GMT -5
I'm going to take this opportunity to preach anew, in general to all, on the "forest and trees" of "seeing" switching schemes.  religionYes, "B" IS supposed to be there and not those other "comfortable" bridge circuit ground connections. This is why I do not like looking at/reviewing a design in wiring (implementation) form, since it is "undersightful" at best (that's why we invented the schematic language). Seeing first in (sub)modular structural form, rather than first taking the overall chassis (wiring) view, leads one to the insight of insight. Using the wiring view leads to one "seeing" a "normal landscape" when it is not. Series structures require one to see that there are signals and returns and NOT signals and grounds. Aside from shields, no wire from a passive pickup and all of its circuit components is ever a ground wire. Some signals/wires just happen to be connected to a ground. (Sub)modular structural form (whether series or parallel, or a combination of both) works easily when one always keeps in mind that grounds are only the final (and usually convenient) resting/connection place of some circuit nodes. With that in mind; While the pot shells CAN be connected to the shield ground (since they are a shielding component), for the series elevated bridge structure, no signal therein can be connected to ground EXCEPT by the Middle/Neck driving Bridge series switching mechanism. The bridge pickup, its DPDT and SP3T internal configuration switches, its tone control circuit, and its volume control are a submodule that must be treated holistically, and only elevated or connected to ground as a single structure. /religionBTW, the Bridge ON switch looks ok.  |
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Post by ChrisK on Jan 15, 2009 20:28:56 GMT -5
A 15 second scan looks ok.
Gotta go, I have to drive 150 miles where it's only -4 degrees (unlike those up in the midweest where it's colder ootside.
And what's with this whole Swedish immigration thing and moving to Minnesoooooota just 'cuz it was like Sweeeeeden?
Hells bells guys, what aboot Florida? There IS a Norwegian settlement in Norge, Virginia.
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Post by ChrisK on Jan 15, 2009 19:58:00 GMT -5
No, the wiring from the DPDT to the SP3T changed.
No, regardless of the position of the SP3T switch, parallel works fine. In series only, the SP3T selects one coil/both coils in series/the other coil.
Don't change it, I actually prefer SP3T - Center OFF since it has 3 positions/throws, and makes contact only in the two end positions.
Yes.
No, it's neither a kill switch nor particularly nifty.
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Post by ChrisK on Jan 15, 2009 19:46:36 GMT -5
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Post by ChrisK on Jan 15, 2009 19:01:12 GMT -5
The one that I really like is #10. Adding 4 push pull pots a'la the LP and a 6-way rotary selector, my P-Rail Switching Scheme will really come alive. Now, there are things in the real design that aren't in what I posted, since....... |
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Post by ChrisK on Jan 15, 2009 18:35:25 GMT -5
Ok Buster, here it is.... While you could use Fun With Toggles & Push-Pull Switches take 2 to do this with binary Tree Switching, you can still do it with your switches as well. The trick is to limit things to where they belong. You want parallel, series, one coil, and the other coil. If you make the DPDT switch do the parallel/series thing, and only let the SPDT Center-OFF switch be active in the series mode, things will be fine. If you do this, things will be just peachy as well as fairly keen.  |
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Post by ChrisK on Jan 14, 2009 21:34:39 GMT -5
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Post by ChrisK on Jan 14, 2009 21:27:23 GMT -5
What does this mod do?
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Post by ChrisK on Jan 14, 2009 21:13:48 GMT -5
Do you have a digital multi-meter?
If not, can you get one?
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Post by ChrisK on Jan 13, 2009 20:14:35 GMT -5
Stick around here, you'll learn how to. |
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Post by ChrisK on Jan 13, 2009 20:09:15 GMT -5
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Post by ChrisK on Jan 13, 2009 11:24:44 GMT -5
Most EMG active pickups have an internal 10K Ohm resistor in series with their output (otherwise you couldn't select two together - the outputs would short).
Yep, this means that their maximum output power transfer occurs with a 10 K Ohm external load. This is 2 VAC across 10 K Ohms or 2^4/10,000 = 0.0004 Watt or 400 uW.
As the external load increases or decreases, the transfered power decreases.
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Post by ChrisK on Jan 12, 2009 19:12:40 GMT -5
Yeah, and who has 0.015 uF caps aboot? If you look at The Demented TeleBlender, switch S2 implements it in increasing cap value order. Arbitrary is. Yes, but if you don't learn fundamentally how to do something, how do you know if the answer is correct (one might have made a data entry error). When one understands the models, one doesn't need to remember the formulaes. Seeing is, well, seeing. That's why we invented the calculus. I guess that you'll owe me another karma point since I've figured how to use it for inductors in parallel as well. ;D ;D |
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Post by ChrisK on Jan 12, 2009 18:54:35 GMT -5
While I don't want to inadvertantly confuse things ( ;D ;D), this will do some interesting things. 3 Single Coils and The "S-None Switch"It's the last picture in the post. It does the following: "For those that want to use the traditional Strat 5-way switch. The Fender Switch alone realizes the following combinations: 1. Bridge 2. Bridge + Middle 3. Middle 4. Neck + Middle 5. Neck With the addition of only a DPDT switch (the S-1 is a 4PDT switch), the following additional combinations are realized, almost like a Fender Am Dlx SSS Strat does: 1. Middle * Bridge 2. Middle * (Bridge + "Special Cap") 3. Middle * "Special Cap" [different, brighter sound than middle alone] 4. Middle * (Neck + "Special Cap") 5. Middle * Neck" If you want to wax esoteric, try the Mike Richardson wiring with phase. I use it in The Padouk Caster. This is what it does ("+" is parallel, "*" is series): Mode switch down A. Bridge (Middle + Neck are shunted) B. Bridge + Middle C. Bridge + Neck D. Middle + Neck E. Neck (Bridge * Middle are shunted) Mode switch up A. Bridge + Middle + Neck B. Bridge * Middle C. Bridge * Neck D. Middle * Neck E. Bridge * Middle * Neck |
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Post by ChrisK on Jan 12, 2009 18:37:35 GMT -5
Don't forget www.digikey.comThey only list 3,712 different polypropylene caps. search.digikey.com/scripts/DkSearch/dksus.dll?Cat=131088&keywords=polypropyleneor www.mouser.comNeither of them rape and pillage on shipping charges. They are both OEM component suppliers so you'll have to get used to not paying exorbitant prices. ;D ;D They also have full data sheets on what they sell, but I must caution that having actual, real, and meaningful data causes most human brains to explode. Especially since words like "warm, deep, full, ethereal, middy, fuzzy, chimey, quacky, vintage, and oxygen-free" are not to be found. |
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Post by ChrisK on Jan 11, 2009 22:54:01 GMT -5
Yes.
Your inquiry seems to indicate that you have little experience with electrical schematics. This diagram is a schematic and not a wiring diagram. Unfortunately, virtually all of it requires a lot of prior knowledge as much is not stated nor shown, but inferred.
That being said, due to the work involved in converting this to a specific wiring diagram, I want to ask if you really want to use this design.
This design will not select the middle pickup alone. Period.
V2 is a converted tone control. It is now an anti-clockwise blender. "10" is the clockwise terminal. "0" is the anti-clockwise terminal. You turn it anti-clockwise to blend out the middle.
Tone is the master tone control.
V1 is the master volume control.
(+) on a pickup is its signal output lead (Hot).
(-) on a pickup is its signal return lead (NOT connected to ground anymore except for the neck pickup in this design).
You get;
1. Neck in series with Middle, with middle shunted/shorted (blended out) by V2. (Bridge pickup is shorted.)
2. Neck (Bridge and Middle pickups are shorted.)
3. Neck in series with Middle in series with Bridge, with Middle shunted/shorted (blended out) by V2.
4. Bridge (Neck and Middle pickups are shorted.)
5. Bridge in series with Middle, with middle shunted/shorted (blended out) by V2. (Neck pickup is shorted.)
Since you will be using pickups in series, 500 K Ohm pots should be used for the master volume and tone controls.
Is this what you want?
What model of guitar and pickups do you have?
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Post by ChrisK on Jan 11, 2009 22:24:53 GMT -5
Well, Chris certainly thinks that he has a more informed view.....
I'm of the opinion that both of these are in appropriate for quality audio circuitry. But then, I'm a snob because I know why these are inferior.
Ceramic is similar in dielectric material to piezo pickups. There have been studies (by real engineers, not audio flufferpuckey merchants) that indicate that the size of a ceramic substrate changes physically when an electrical charge is placed across it. This changes back while the charge dissipates. This is the piezo part. (Remember discussions a'board about a piezo crystal being predominantly capacitive in characteristic?)
In other words, there is a memory effect that affects the sound quality thru a delayed (and hence non-linear) action.
Ceramic bypass capacitors such as a Z5U type can have significant leakage (which manifests itself as a parallel resistance effect) as well as a -20/+80% tolerance.
Mylar capacitors are also not high quality. They have what's known as dielectric absorption. The complete charge is delayed in its ability to be discharged into a load once the applied charge is removed. Again, a non-linear memory effect. This is most evident in high voltage capacitors (such as 10 KVDC) which come shipped with a shorting wire wound across both terminals. After Hi-Pot testing, the cap is shorted. Even if the voltage is zero, if left unshorted, the charge can eventually climb to hundreds of volts.
Since these effects are time-based, the effect varies with frequency.
It's similar to a motor is a generator, a generator is a motor (DC et al).
Now, there are some excellent mylar and ceramic capacitors. I know where to get them and how to read their spec sheets.
However, most folk are not electrical engineers and most guitar parts vendors are not going to sell the best parts, but the cheapest parts. Most of the generic mylar or ceramic 0.022 caps used in the industry cost less than $0.05 in thousands. They're sold for $0.25 to $1.00.
I tend to use OEM polycarbonate or polypropylene caps because I can, since I have access and knowledge regarding their electrical specifications.
Most capacitors used in vintage guitars were used not because they were excellent capacitors, but because they were cheap capacitors. The defects native to such are often the effects cherished for their vintage sound.
I can tell you if a cap is lousy or good; I can't tell you if it will definitively sound lousy or good in your application.
But, John is most correct; unless one can immediately A/B switch between components under test, during THE SAME AUDIO EVENT (such as one sustaining string pluck), any comparison is highly suspect and likely hydrogenated felderpucky.
(Never underestimate the ability of a human to rationalize, especially if they've spent coin serious on audio flufferpucky.)
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Post by ChrisK on Jan 11, 2009 0:21:26 GMT -5
Do you happen to know the model and year of the guitar? Do you happen to have pics that you can post? What part is broken on the vibrato? If you know the model and year, you may be able to get replacement parts for it from a Fender authorized repair center. www.fender.com/support/japanese_instruments.phpFrom the Fender site; "Note: Most of our older guitar parts lists, wiring diagrams and switching control function diagrams predate formatting which would allow us to make them available on this site as PDF files. If you do not find the list or diagram for your specific instrument on this page, we may still be able to furnish you with a "hard" copy from our archive. You may check the availability of older material by contacting Fender's Consumer Relations Department by phone at 480.596.7195 or by e-mail at consumerrelations@fender.com. If we have the document you seek, we're happy to send you a copy. All hard copy parts lists, wiring diagrams and switching control function diagrams are $5 each (shipping and handling included). Please send a check or money order for $5 (U.S.) for each separate list or diagram you require, along with a letter detailing your request and the specific documentation you require, to: CUSTOMER SERVICE FENDER MUSICAL INSTRUMENTS 8860 E. CHAPARRAL ROAD, SUITE 100 SCOTTSDALE, ARIZONA 85250, U.S.A." |
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