201. What is the basic construction of a magnetic pickup?
Depending on the design of the pickup there are a few basic parts in which pickups are made. A. a permanent magnet B. pole pieces C. coil or coils D. bobbin or flatwork E. component support
A. A permanent magnet can be made of several types of material IE: Alnicos & Ceramic
being the most common. There are several grades of Alnico’s and Ceramics
B. Pole pieces are usually made of rod magnets like in Fender single coils and a soft iron material used to direct the magnetic field.
C. Coils are wound with several thousand turns. Depending on the diameter of the
magnet wire, the number of turns and shape of the coil will help determine the sound and output of the pickup. More turns will increase the output and make the pickup sound less bright Less turns will decrease the output and make the pickup sound brighter. In a humbucking pickup two coils can be connected in series or parallel. Humbuckers usually have a fatter sound than single coils.
D. Bobbins and flatwork can be made from a number of materials ranging from paper, bakelite, nylons, vulcanized fibre, plastics and other non-conductive materials. Bobbins are used to hold the wound coil stable and keep it from changing shape. After a coil is wound and held to shape with a bonding material such as wax or varnishes the tooling of an air coil can be pulled apart leaving the coil without a bobbin. The air coil can then be insulated with a material such as tape and then be inserted into a cover with magnet, iron load or pole pieces.
E. Component support: After the bobbins are wound the components are all supported by means of a bottom plate, cover or mechanical assembly. The bobbins on Gibson style humbucker are held in place by 4 screws to hold the bobbins, magnet and unit together. A cover is used also holds the components in place. Gibson Mini-humbuckers use no mounting screws and need a cover to keep everything in place. In most Fender style single coil pickups the magnets are pressed into the flatwork and wound to the desired number of turns and winding direction. The magnets are magnetized either north or south polarity and the pickup is secured into a mounting ring, plate or pickguard.

202. Do you use thinner gauge of magnet wire to get more turns in the same amount of space or are there other advantages?
If you are using a bobbin with a limited amount of space then you can either use a thinner insulation or use the next thinner 1/2 or full gauge magnet wire. As the number for magnet wire increases the diameter decreases. Using a smaller diameter magnet wire will allow you to wind with an increased number of turns will give you more output with less highend. If you use 7600 turns with 42 gauge magnet wire the DC resistance can be 5.8K Ohms...If you use 7600 turns of 43 gauge magnet wire the DC resistance can be 7.5K Ohms. Even with the extra space, adding turns will really increase the DC resistance. Using the 43 gauge magnet wire and adding another 1000 turns will increase the DC resistance as much as a thousand ohms or possibly higher. As the coil diameter gets larger, the winding length of each turn slightly increases the DC resistance even more.

203. Affects of wax potting. Why is it called “potting?” Why is it used on some pickups and not others.
Wax potting is done for several reasons. It reduces unwanted mechanical vibration within the pickups components like screws, metal spacers, magnets etc. Another important reason is to keep the moisture from penetrating the coil and reduces moisture that could eventually cause the poles to rust on single coil pickups. Single coil pickups after time have a problem with Inner coil pole corrosion (ICPC). Waxing helps keep the insulation protected and if there ever was coil damage, it can be easily repaired. When using varnishes or epoxy potting solutions it usually mean the coils can never be successfully repaired without extreme damage to the coil or bobbin.
The term potting most likely came about because pots were used as in making candles when they were dipped in and out. The pickups are usually wax dipped in an open pot containing hot wax. (Do not try to do this without proper procedures! Extreme Danger!) Gibson style pickups like the P-90, Humbucker and Melody Maker’s originally didn’t have wax potted coils. The pickups had a higher DC resistance and lower resonant frequency than the Fender Telecaster or Stratocaster style pickup. Also the Gibson coil was insulated from the pole pieces by means of a fabricated or molded bobbin. The Fender pickup has the magnet wire wound directly to the rod pole pieces. The amplification used in the 40’s through the early 60’s was not as loud as amplifiers used today and pickups didn’t seem to feedback as much then as compared to today with the use of pre-amps and overdrives.

204. What effect does magnet wire gauge have on DC resistance and resonant peak.
As a general rule..using the same number of turns on a pickup and different gauges of magnet wire will give you different DC resistance’s and Different resonant peaks. Winding a coil with 8,000 turns of 42 AWG will sound brighter and have a higher resonant peak than a coil wound with 8,000 turns of 43 AWG magnet wire.

205. What are the advantages and disadvantages of series vs. parallel wiring?
I would say there are advantages to having both series and parallel wiring. You can get interesting tones when using more than one coil. When using two coils, they can be combined in series, parallel, humbucking in phase and out of phase. When two coils are hooked up in series you have maximum DC resistance of both coils added together. When in parallel the coils are divided by the sum of 2 . When the two coils are hooked up in series you have maximum fullness and output in the pickup. When in parallel you get a nice mid tone out of them. Using a standard 5 way lever switch on a Fender Stratocaster, the 2 & 4 position put the pickups in parallel with each other. The 2 & 4 position if often mistakenly called the “out of phase” position. The pickups are connected in parallel and are properly in phase.

206. Why did humbuckers originally have metal covers?
Gibson used covers on their original humbuckers designed by Seth E. Lover. It was use in combination with the two coils to reduce unwanted 60 cycle hum often associated with single coil pickups. Seth used nickel silver covers to help eliminate unwanted outside electrical interference from entering the coil. The combination of two coils hooked up 180 degrees out of phase and two magnetic fields (north & south) the coils are covered to give maximum coil protection for unwanted electrical interference. The nickel silver cover has less capacitance which can cut the higher frequencies in the pickup. It gives added shielding to the coils and to give the coils a protective and cosmetic covering for the pickup.

207. Where did the idea of removing the covers originate? How does removing the cover affect the sound?
The first player I ever saw that removed the covers from their humbuckers was Jeff Beck during the mid 60’s while playing in the Yardbirds. Jeff removed the covers on his sunburst Les Paul to get the pickups closer to the strings thus increasing the output of the pickups. It also reduced the microphonic feedback in the pickups (Gibson didn’t wax pot the pickups back then). There is also an increased risk of pickup squeal as the amplifiers were getting much louder. As the amplifier wattage got higher and higher, players started to complain about the pickup feedback problems. Many players still keep the covers on their old guitars like Billy Gibbons from ZZ Top. Removing the covers will give the pickup a little higher fidelity and allows the pickups to get closer to the strings that can also increase the volume of the pickup. If the cover is not properly potted with the pickup, playing at higher volumes will increase the risk of feedback in the pickup.

208. What can you do to reduce the chances of microphonics and feedback when using covered humbuckers?
The best way to reduce microphonics in a pickup is to make sure the components inside the pickup are firmly secure and I believe using a warm soft wax potting to help reduce unwanted feedback from the pickup. The wax helps reduce mechanical vibrations and gaps within the components. I don’t believe in potting or encapsulating pickups and especially vintage pickups in a epoxy solution. Epoxy potting is permanent and future repair or modification can be extremely difficult if not possible. Extreme care and safety should be taken when wax potting pickups. The vapor from the wax is extremely flammable and proper procedures should be followed.

209. How close does a split coil humbucker sound to a good single coil tone?
Standard humbuckers have two coils that normally pick up two areas of the string. When you split a pickup you cut out one coil and eliminate the current generated from that area of the string. The split pickup now uses one coil and 1/2 of the total turns when combined with the other coil in series. If you spit a pickup that is normally 8 K ohms, you now have a pickup that is 4 K ohms. You will have less output but a higher resonant peak or brighter sounding pickup. Trying to simulate a typical single coil like a Stratocaster will be difficult to achieve due to many factors. The number of turns, the shape of the coil and the type magnets used to name a few. When you split a humbucker you reduce the total turns within the pickup by half, you generate less output when using one coil and the pickup will be thinner and brighter sounding. You will simulate the single coil pickup because you are only using one side of the coil and one string area. Also when you split the coil you will notice an increase in 60 cycle hum. With some fancy wiring combinations you can come up with several unique guitar sounds.

210. Why does a guitar hum if standing by an amp but hums less when you turn to a different direct.
The hum you hear in your amplifier is usually caused by stray magnetic fields generated from the output and power transformers in your amplifier. It is commonly called 60 cycle hum and is one of the major problems that occur with single coil pickups. There are various single coil sized humbucking pickups on the market that can be used to reduce unwanted hum in your guitar With standard single coil pickups as you change direction to your amp, you change the phase angle in relationship to your instrument. If you are near computer monitors, radiation and internal electronics can transmit unwanted signals into your instrument.

211. Why does my guitar buzz electrically when I'm not touching the strings?
Think about all the stray electronic fields such as radio waves, cellular phones and many stray magnetic fields you can’t see. Guitar strings act like an antenna and pickup the various stray magnetic fields and when you touch the strings, the unwanted buzz is usually reduced as long as the strings are grounded to the controls. Having the strings grounded to the controls can increase the risk of electrical shock if you accidentally touch a system with reverse polarity.

212. Why is the brass metal plate used on a Telecaster?
The plate used on the bottom of a Telecaster is made of a cold rolled steel and is copper plated to help keep the plate from rusting and the copper plating makes it easier to solder the ground wire.

213. Should pickups be rewound if they don't work?
The majority of pickups that don’t work can usually be repaired and restored if you take the time and find a qualified repairman. Many times there are cold solder joints that can be carefully heated, broken magnet wire can be spliced if the outer coil is broken. You don’t always need your pickups rewound and have it checked by a reputable repairman.

214. What are the patent numbers for popular guitar pickups?
A Patent is a government grant that allows the inventor to make, use and sell for a certain amount of time. It gives the inventor exclusive right to an invention or discovery. To be eligible for a patent, an invention must be new, useful or improvement of an existing patent. All patents other than design patents give the inventor control over an invention for 17 years. He must pay and protect his own invention which can be quite costly. Design patents are issued for 3 1/2, 7 or 14 years at the inventors option. A patent cannot be renewed except by a special act of Congress. It takes an average of two years for the U.S. Patent and Trademark Office to issue a patent. Manufactures put a “Patent Applied For” as soon as a patent is applied for to get the newly invented product on the market. The patented article may be marked with either a patent number or just be marked “Patented”. If an invention is copied without the owners permission, it is called infringement and the owner may sue for damages. Trademarks and Patents must be issued for each country where you need to be protected.

215. What is a guitar pickup?
An electromechanical device for sensing the string vibration as it is plucked causing electrical current to be generated which is then amplified and reproduced over a speaker. The output of an electric pickup, depending on its design, may be proportional to the velocity or amplitude of the moving string.

216. What is the basic construction of a magnetic pickup?
Depending on the design of the pickup there are a few basic parts in which pickups are made. A. a permanent magnet B. pole pieces C. coil or coils D. bobbin
A. A permanent magnet can be made of several types of material I.E.: Alnicos & Ceramic being the most common. There are several grades of Alnicos and Ceramics
B. Pole pieces are usually made of rod magnets like in Fender single coils and a soft iron material used to direct the magnetic field.
C. Coils are wound with several thousand turns. Depending on the diameter of the
magnet wire, the number of turns and shape of the coil will help determine the
sound and output of the pickup. More turns will increase the output and make the pickup sound less bright Less turns will decrease the output and make the pickup sound brighter. In a humbucking pickup two coils can be connected in series or
parallel. Humbuckers usually have a fatter sound than single coils.
D. Bobbins can be made from a number of materials ranging from paper, bakelite, nylons, vulcanized fibre, plastics and other nonconductive materials. Bobbins are used to hold the wound coil stable and keep it from changing shape. After a coil is wound and helded to shape with a bonding material such as wax or varnishes the tooling fo an air coil can be pulled apart leaving the coil without a bobbin. The air coil can then be insulated with a material such as tape and then be inserted into a cover with magnet, iron load or pole pieces.

217. Where can I locate manufacturers that make pickups?
Here are some of the current pickup manufactuers that make many models.
Seymour Duncan Pickups-5427 Hollister Ave.-Santa Barbara,Ca. 93111 805-964-9610
L.R. Baggs Co.-483 North Frontage Road-Nipomo,Ca. 93444 805-929-9545
Barcus-Berry, Inc.-5381 Production Drive-Huntington Beach, Ca. 92649 714-898-9211
Bartolini Pickups-2133 Research Drive #16-Livermore, Ca. 94550 510-443-1037
Dean Markley Electronics-3350 Scott Blvd. #45-Santa Clara, Ca.95054 408-988-2456
DiMarzio, Inc.-1388 Richmond Terrace-Staten Island, NY 10310 718-981-9286
EMG, Inc.-P.O. Box 4394 Santa Rosa, Ca. 95402 707-525-9941
Fishman Tranducers-5 Green Street-Woburn, MA 01801 617-938-8850
George L's Musical Products-P.O. Box 238-Madison, TN 37116 615-868-6976
Lindy Fralin Pickups-1236 Richie Hwy.-Suite 201-Arnold, MD. 21012 410-544-7095

218. What are the advantages and disadvantages of series vs. parallel wiring?
When two coils are hooked up in series you have maximum DC resistance of both coils added together. When in parallel the coils are divided by the sum of 2 (give specific information). When the two coils are hooked up in series you have maximum fullness and output in the pickup.

219. Why did humbuckers originally have metal covers?
Gibson used covers on their original humbuckers designed by Seth E. Lover. It was use in combination with the two coils to reduce unwanted 60 cycle hum often associated with single coil pickups. Seth used nickel silver covers to help eliminate unwanted outside electrical interference from entering the coil. The combination of two coils hooked up 180 degrees out of phase and two magnetic fields (north & south) the coils are covered to give maximum coil protection for unwanted electrical interference. The nickel silver cover has less capacitance which can cut the higher frequencys in the pickup. It gives added shielding to the coils and to give the coils a protective and cosmetic covering for the pickup.

220. How do different cover materials affect the sound (nickel-plated brass vs. solid nickel Silver vs. gold plated etc.?
The chart below will give you examples of how various materials for covers affect the frequency of a pickup. Nickel silver works the best and aluminum and brass covers reduce the frequency in the pickup. The cover will also affect the Q of the coil.

221. Where did the idea of removing the covers originate? How does removing the cover affect the sound?
The first player I ever saw that removed the covers from their humbuckers was Jeff Beck during the mid 60’s while playing in the Yardbirds. Jeff removed the covers on his sunburst Les Paul to get the pickups closer to the strings thus increasing the output of the pickups. It also reduced the microphonic feedback in the pickups (Gibson didn’t wax pot the pickups back then). There is also an increased risk of pickup squeel as the amplifiers were getting much louder. As the amplifier wattage got higher and higher, players started to complain about the pickup feedback problems. Many players still keep the covers on their old guitars like Billy Gibbons from ZZ Top. Removing the covers will give the pickup a little higher fidelity and allows the pickups to get closer to the strings that can also increase the volume of the pickup. If the cover is not properly potted with the pickup, playing at higher volumes will increase the risk of feedback in the pickup.

222. What can you do to reduce the chances of microphonics and feedback when using covered humbuckers?
The best way to reduce microphonics in a pickup is to make sure the components inside the pickup are firmly secure and I believe using a warm soft wax potting to help reduce unwanted feedback from the pickup. I don’t believe in potting or encapulating (epoxy) vintage pickups. Epoxy potting is permanent and future repair or modification can be extremely difficult if not possible with this kind of potting. Extreme care and safety should be taken when wax potting pickups. The vapor from the wax is extremely flamable and proper procedures should be followed. (see insert)

223. How close does a split coil humbucker sound to a good single coil tone?
Standard humbuckers have two coils that normally pick up two areas of the string. When you split a pickup you cut out one coil and eliminate the current generated from that area of the string. The spilit pickup now uses one coil and 1/2 of the total turns when combined with the other coil in series. If you spit a pickup that is normally 8k ohms, you now have 4k ohms. You will have less output but a higher resonant peak or brighter sounding pickup. Trying to simulate a typical single coil like a stratocaster will be difficult to achieve due to many factors. When you split a humbucker you reduce the total turns within the pickup by half, you generate less output when using one coil and the pickup will be thinner and brigher sounding. You will simulate the single coil pickup because you are only using one side of the coil and one string area. Also when you split the coil you will notice an increase in 60 cycle hum.(insert chart showing the output of a pickup when split)

224. What kind of plastic where the first Fender Stratocaster pickup covers made of? Pete Quigley-Palm City, Florida
Doing research and talking to George Fullerton and plastic molders I found that the plastic was called Cycolac brand polymers and is from a unique family of ABS (Acrylonitrile-Butadiene-Styrene) thermoplastic resins produced by the Marbon Chemical Division of Borg-Warner. The info I found was from 1963 and at that time the plastic came in nine major formulations. After a short time Fender started using a nylon based material for it’s injected molded covers. Cycolac brand plastic is well suited for a wide range of consumer and industrial applications. It didn’t work to well for the constant abuse from strumming and picking and the covers became brittle and pieces would crack and chip off. Depending on the formulation the plastic worked well in other applications. I think it was a combination of molding and the thinness of the walls that caused it to fail upon use. Cycolac brand polymers also offered seven other product improving advantages.
1. Good electrical properties: It had low water absorption rate plus its uniform dielectric constant and power factors. The electrical properties didn’t do to much but the low moisture absorption rate helped on those hot humid nights.
2. Resistance to chemicals: It is highly corrosion resistant and offers protection against alkalizes, salt solutions, oils and mild acids.
3. Lightweight: The ABS resins are the lightest of all truly rigid thermoplastics, with a specific gravity as low as 1.02.
4. Wide color range: It’s available in hundreds of bright, sparkling colors, tints and shades. It has superior resistance to stains and doesn’t discolor normally.
5. Dimensional Stability: Cycolac offers excellent dimensional stability even under extreme temperatures.
6. High gloss finish: The ABS polymers mold to a luxurious satiny finish. The smooth hard surface resists scratching and marring and retains it’s natural sheen.
7. Ease of finishing: Cycolac can be calendered into a grained, leather like finish and can be lacquered, enameled, printed on and can be vacuum metallized.
Cycolac plastics have been used on MacGregor football helmets, Western Electric Telephones, Remington typewriters, radios, power tools, photo copy machines, luggage, office equipment, baseball helmets, fishing reels, furniture, television cabinets, toys, pipe fittings and musical instrument components.
Cycolon brand ABS resins have high levels of performance in critical areas such as chemical resistance, rigidity, hardness and surface gloss. Cycolon brand ABS resins injection mold easily and exhibit good mold flow for intricate parts.
ABS Polymers Grade and Characteristic
Cycolac:
Grade H: Maximum toughness good for injection molding and sheet extrusion
Grade L: Maximum toughness at low temperatures and good for sheet extrusion
Grade T: Maximum flow and good for injection molding.
Grade GS: High Modulus-GSE is for sheet extrusion, GSM is for injection molding, and GSS is good for shape extrusion.
Grade X7: High heat and is good for injection molding.
Grade SF: Semi-flexible extruded profile and is good for shape extrusion.
Grade B: ABS type I is for pipe resins and is available in black only.
Grade LL: ABS type I grade 2 also for pipe resin and only available in black.
Grade C: ABS type II is for pipe resin and is available in black only.
Cycrolon:
Grade A: Medium impact and AM is for injection molding and AE is sheet extrusion.
Blendex Reinforcing Modifiers: Available in powder form only
Grade 101: General purpose.
Grade 201: High impact strength.
Grade 301: Maximum low temperature and toughness.
Grade 401: Maximum clarity.

225. How is Vulcanized fibre made that’s used for pickup bobbins and coil forms used by Fender, Duncan, Fralin and older Gibson P-90 and Guild bobbins? Fred Thompson- Nashville, Tennessee
George W. Creighton Jr. who was the Material Engineer for the National Vulcanized Fibre Co. writes. Vulcanized fibre is produced in a number of different grades. The final grade depends upon the starting material. Saturating a grade of absorbent paper is the base material for Vulcanized fibre and may be made form cotton rags or wood pulp of high alpha cellulose content. The paper is immersed in a zinc chloride solution, the resulting chemical action causes the individual cellulose fibres to swell and become covered with a layer of “gel.” Plies of “gelled” paper are bonded together under controlled heat and pressure to produce sheets of desired thickness. Vulcanized fibre tubes are made on round mandrels and rods are produced by cross-sectional strips cut from sheets and turned to the required diameter. Vulcanized fibre can be formed by cutting, punching, tapping, milling, shaping, sanding, etc. Methods are described in the (NEMA) National Electrical Manufacturers Association publications. Vulcanized fibre is often used for insulation’s in transformers and older style drum cases. Fender style bobbins used a black Vulcanized fibre till the mid 60’s than a light gray and in the 70’s a darker gray. Since the 80’s and 90’s Fender has reintroduced the black Vulcanized fibre. They are doing a great job with the Vintage Re-issue instruments. Normally the Vulcanized fibre used for the top of the bobbin is .062” thick and the bottom uses .093” thick. Early Broadcaster, Telecaster, No-Caster and Esquire bobbins used a .062” and early on changed the .093”. I believe it was changed due to the pressure from the 3 mounting screws on the Broadcaster, Telecaster, No-Caster and Esquire easily warped the thinner flatwork so Leo Fender decided to use thicker Vulcanized for added strength over time. The thicker flatwork helped keep it tighter to the pole pieces and helped avoid the bobbin from falling apart.