Provided are: a magnetic recording medium including a non-magnetic support and a magnetic layer containing a ferromagnetic powder, in which the ferromagnetic powder is an ε-iron oxide powder, a vertical switching field distribution SFD of the magnetic recording medium is 0.20 or more and 3.00 or less at a measurement temperature of 25° C., and an inclination of SFD obtained from SFD at a measurement temperature of 10° C., SFD at a measurement temperature of 25° C., and SFD at a measurement temperature of 40° C. is 0.003° C..sup.-1 or more and 0.080° C..sup.-1 or less; a magnetic tape cartridge including the magnetic recording medium which is a magnetic tape; and a magnetic recording and reproducing device including the magnetic recording medium.

Provided are: a magnetic recording medium including a non-magnetic support and a magnetic layer containing a ferromagnetic powder, in which the ferromagnetic powder is an ε-iron oxide powder, H.sub.0.2 of the magnetic recording medium is 5,000 Oe or more and 40,000 Oe or less at a measurement temperature of 25° C., and an inclination of H.sub.0.2 obtained from H.sub.0.2 at a measurement temperature of 10° C., H.sub.0.2 at a measurement temperature of 25° C., and H.sub.0.2 at a measurement temperature of 40° C. is −100 Oe/° C. or more and −5 Oe/° C. or less; a magnetic tape cartridge including the magnetic recording medium which is a magnetic tape; and a magnetic recording and reproducing device including the magnetic recording medium.

A magnetic tape including a timing-based servo pattern, in which the magnetic tape is used in a magnetic tape device in which a total number of data tracks is 8705 or more in conversion of a magnetic tape having a width of ½ inches, and ΔPNL of the timing-based servo pattern is 10.0% or less of a track pitch. A magnetic tape cartridge including the magnetic tape, and a magnetic tape device including a magnetic tape, in which a total number of data tracks is 8705 or more in conversion of a magnetic tape having a width of ½ inches, the magnetic tape includes a timing-based servo pattern, and ΔPNL of the timing-based servo pattern is 10.0% or less of a track pitch are provided. The ΔPNL indicates an amount of deviation of the timing-based servo pattern from linearity.

A magnetic tape including a timing-based servo pattern, in which the magnetic tape is used in a magnetic tape device in which a total number of data tracks is 8705 or more in conversion of a magnetic tape having a width of ½ inches, and ΔPNL of the timing-based servo pattern is 10.0% or less of a track pitch. A magnetic tape cartridge including the magnetic tape, and a magnetic tape device including a magnetic tape, in which a total number of data tracks is 8705 or more in conversion of a magnetic tape having a width of ½ inches, the magnetic tape includes a timing-based servo pattern, and ΔPNL of the timing-based servo pattern is 10.0% or less of a track pitch are provided. The ΔPNL indicates an amount of deviation of the timing-based servo pattern from linearity.

A hexagonal strontium ferrite powder, in which an average particle size is 10.0 to 25.0 nm, a content of one or more kinds of atom selected from the group consisting of a gallium atom, a scandium atom, an indium atom, and an antimony atom is 1.0 to 15.0 atom % with respect to 100.0 atom % of an iron atom, and a coercivity Hc is greater than 2,000 Oe and smaller than 4.000 Oe. A magnetic recording medium including: a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, in which the ferromagnetic powder is the hexagonal strontium ferrite powder. A magnetic recording and reproducing apparatus including this magnetic recording medium.

A hexagonal strontium ferrite powder, in which an average particle size is 10.0 to 25.0 nm, a content of one or more kinds of atom selected from the group consisting of a gallium atom, a scandium atom, an indium atom, and an antimony atom is 1.0 to 15.0 atom % with respect to 100.0 atom % of an iron atom, and a coercivity Hc is greater than 2,000 Oe and smaller than 4.000 Oe. A magnetic recording medium including: a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, in which the ferromagnetic powder is the hexagonal strontium ferrite powder. A magnetic recording and reproducing apparatus including this magnetic recording medium.

A cartridge memory is a cartridge memory used in a recording medium cartridge and includes an antenna section that induces an induced voltage by means of electromagnetic induction, a load modulation section including a load whose magnitude is variable, and a control section that measures the induced voltage and controls the load modulation section on the basis of the measured induced voltage.

A cartridge memory is a cartridge memory used in a recording medium cartridge and includes an antenna section that induces an induced voltage by means of electromagnetic induction, a load modulation section including a load whose magnitude is variable, and a control section that measures the induced voltage and controls the load modulation section on the basis of the measured induced voltage.

In the magnetic recording and reproducing device, a distal end width of the first magnetic pole in the recording element is substantially the same as a distal end width of the second magnetic pole; the reproducing element width of the reproducing element is equal to or less than 0.8 μm; and in the magnetic recording medium, a number distribution A of equivalent circle diameters of a plurality of bright areas in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer with a scanning electron microscope at an acceleration voltage of 5 kV, and a number distribution B of equivalent circle diameters of a plurality of dark areas in a binarized image of a secondary electron image obtained by imaging the surface of the magnetic layer with a scanning electron microscope at an acceleration voltage of 2 kV satisfy predetermined number distribution, respectively.

A servo writer includes a running unit that sends a tape-like magnetic recording medium out from a cartridge, winds up the sent out magnetic recording medium, and runs the magnetic recording medium; an erasing unit that erases a first servo pattern formed in the magnetic recording medium that runs; a head that writes a servo signal in the running magnetic recording medium from which the first servo pattern is erased and forms a second servo pattern; and a control unit that controls the head so that the servo signal is written in at least one period of an accelerated running period and a decelerated running period of the magnetic recording medium, and forms the second servo pattern that does not satisfy a standard in the magnetic recording medium.