Abstract: A voltage compensation system for an A.C. power line supplying one or more air conditioners, a telephone system or other telecommunication system, a battery charger, or some other utilization system that should have an input voltage within a given normal range. The voltage compensation system includes a transformer unit containing a transformer having at least two windings coupled electromagnetically by a transformer core; one of those windings preferably is in two segments that are connectable in series or in parallel. One winding is connected to an input terminal and to an output terminal. The other winding adds to the A.C. line voltage when the line voltage drops below a low voltage threshold and/or subtracts from the line voltage when the A.C. line voltage exceeds a high voltage threshold. If the A.C. line voltage is in the range required by the utilization system, the other transformer winding is effectively shorted out or otherwise disconnected.

Abstract: A voltage compensation device for a two-conductor A.C. power line supplying one or more air conditioners, a telephone system or other telecommunication system, or some other utilization system that requires an input voltage within a given range. The device includes a transformer having electromagnetically coupled primary and secondary windings with the primary and secondary each connected to at least one output terminal. One winding is connected to add voltage to the A.C. line voltage when the line voltage drops below a given low voltage threshold, and in bucking (subtractive) relation when the A.C. line voltage exceeds a given high voltage threshold. When the A.C. line voltage is in the range required by the utilization system, the one winding is effectively shorted out or otherwise disconnected. A sensor for the line voltage actuates one or more relays connected to the transformer to effect the desired compensation action.

Abstract: A signal blender that combines the pickup signals generated by three pickups for a musical instrument (e.g., a guitar) in plural combinations and multiple amplitudes to develop a blend signal. The device comprises a main blending resistance with plural connection taps, one for each pickup when the main resistance is a complete 360.degree. ring, one more tap if the main resistance is less than 360.degree.. Each pickup is connected to a tap. A rotary contact engages the main resistance to generate the blend signal; the blend signal is applied to an output amplifier.

Abstract: An electrical connector jack for a conventional two-conductor electrical connector plug; the plug is inserted into the jack in a given direction to connect a signal source to an amplifier with minimal or no noise when the connection is made. The plug has concentric electrically isolated tip and ring electrodes, with the tip projecting beyond the ring in the direction of insertion. The jack includes two signal contacts (one may be grounded) engageable individually with the tip and ring electrodes of the plug when the plug is fully inserted into the jack; these signal contacts are electrically connected to a signal source such as a guitar pickup. A shorting contact engages and interconnects the tip and ring electrodes until the plug is fully inserted. The signal contacts and the shorting contact may have a common insulator support.

Abstract: Surge protection for a data transmission line, typically a telephone line including two data signal conductors, incorporates a primary protector circuit for high voltage, high energy surges and a secondary protector circuit for low voltage surges. The primary protector circuit includes a normally non-conductive "breakdown" or "crowbar" device having a high breakdown voltage, a solid-state triac, or a thyristor, driven conductive by a surge exceeding its breakdown voltage; the crowbar device is connected from one or both conductors to ground. An inductance is connected in the circuit to extend the time in which the circuit reduces a surge to near zero voltage, and thus dissipates power from the surge. The second protector circuit includes at least one avalanche diode, Zener diode, or other threshold device in parallel with the primary protector circuit.

Abstract: An electromagnetic pickup for a musical instrument, such as a guitar, strung with ferromagnetic strings, comprises an elongated laminated ferromagnetic (steel) core long enough to span all of the strings; there are at least four and usually six thin steel laminations in the core. An electrical pickup coil is wound in a coil form, usually plastic, that encompasses the core, and a vertically magnetized main permanent magnet engages the bottom edge of the core. The magnet is preferably formed of a resin impregnated with magnetic particles, is magnetized transversely, and maintains the core at a given polarity. A housing encloses the core, the coil, and the main magnet and provides for mounting the pickup in spaced relation to the strings so that the magnetic field encompasses the strings and string movement generates electrical signals to the coil. Preferably, there are additional permanent magnets to shield the sides of the core. Dual-coil humbucker embodiments of the pickup are described.

Abstract: An electromagnetic pickup for a musical instrument (e.g. a guitar) having a plurality of ferromagnetic strings coplanar and parallel with each other, the pickup being adapted to be mounted adjacent to but spaced from the strings includes an elongated electrical pickup coil having a longitudinal central opening, the opening having a length at least as great as the span S of the strings. The pickup also includes an elongated main permanent magnet having a length L such that L>S and an elongated ferromagnetic shell having a length at least as great as S. The main permanent magnet, the pickup coil, and the shell are assembled together in an electromagnetic pickup assembly in which at least one side of the pickup coil is enclosed by the shell, and the main permanent magnet is parallel to the central opening of the coil; the assembly generates a magnetic field which encompasses at least one portion of the pickup coil.

Abstract: An electromagnetic pickup for a musical instrument, such as a guitar, strung with ferromagnetic strings, comprises an elongated ferromagnetic (steel) core of U-shaped or double U-shaped transverse cross-section. An electrical pickup coil in a non-magnetic coil form encompasses one core leg; transversely magnetized main permanent magnets engage the top edges of the core legs. The magnets, which may be integral with each other, are preferably formed of a resin impregnated with magnetic particles; they maintain adjacent core legs at opposed polarities. The main magnets may be mounted in or on the top of a housing that encloses the core and the coil; the housing provides for mounting the pickup in spaced relation below the strings so that the pickup produces a magnetic field that encompasses the strings and string movement generates electrical signals in the coil. There may be additional permanent magnets to shield the coil. Dual-coil humbucker embodiments of the pickup are described.

Abstract: An electromagnetic pickup assembly for a musical instrument, such as a guitar, strung with ferromagnetic strings, comprises an elongated high permeability ferromagnetic (steel or iron) core long enough to span all of the strings. An elongated, annular electrically conductive pickup coil is wound in a coil form, usually plastic, that encompasses the core. An elongated, unitary, annular permanent magnet closely encompasses all sides of the coil; it is transversely magnetized to maintain the core and the coil in a magnetic field of a given polarity. There is no permanent magnet engaging the core. A housing or other mounting is used to mount the core, the coil, and the permanent magnet in spaced relation to the strings so that the pickup generates a magnetic field that encompasses all of the strings, whereby movement of any string or combination of strings generates electrical signals in the coils. The housing may include a steel shell around the permanent magnet.

Abstract: An electromagnetic pickup assembly for a musical instrument, such as a guitar, strung with ferromagnetic strings, comprises two elongated high permeability ferromagnetic (steel or iron) cores each long enough to span some but not all of the strings; preferably, there are several thin steel laminations in the core. Two electrically conductive pickup coils are wound in coil forms, usually plastic; one such coil form encompasses each core. There are two vertically magnetized main permanent magnets, each having a high energy product (BxH); each main magnet engages the bottom edge of one core and maintains that core at a given polarity. A housing or other mounting members mount the cores, the coils, and the main permanent magnets in spaced relation to the strings so that the pickup generates two magnetic fields that, together, encompass all of the strings, whereby movement of any string or combination of strings generates electrical signals in the coils.

Abstract: An add-on device that modifies the operating characteristics (e.g., amplitude, frequency response, "sustain") of the output signal of an electromagnetic pickup for a stringed musical instrument, such as a guitar with steel strings; the modification device includes one or more transversely magnetized thin, flat permanent magnets. The signal modification device covers most or all of the top surface of an electromagnetic pickup. In one form the signal modification device comprises a thin, flat permanent magnet member formed of resin impregnated with particulate permanent magnet material and magnetized transversely to its thin dimension, either uniformly or in a predetermined pattern; in another form the device includes one or more discrete thin, flat permanent magnets for each instrument string, mounted on a base sheet that may also have permanent magnet characteristics or that may be non-magnetic.