ROTARY HEAD LEVEL DIFFERENCE ADJUSTOR AND MAGNETIC RECORDING AND REPRODUCING DEVICE PROVIDED WITH AUTOMATIC HEAD LEVEL DIFFERENCE ADJUSTING MECHANISM

摘要

PURPOSE:To highly accurately adjust the level difference of plural heads by preparing an alternate leaked magnetic flux generating means, detecting leaked magnetic flux by respective rotary heads set up to a reproducing mode and adjusting respective height of the heads so that the detecting levels of respective rotary heads are set up to a prescribed value. CONSTITUTION:The rotary heads 4a, 4b are driven in the reproducing mode and the current of a certain frequency band is generated from an alternate current generator 31 and supplied to the leaked magnetic flux generator 30 to generate leaked magnetic flux 38. The generator 30 is oppositely approached to the rotary heads 4a, 4b by a moving board 37 and moved in the arrow D direction. In accordance with the approach of the generator in the D direction like (a)-(b)-(c), the detecting levels of the heads 4 are increased and a linearly approximated part is generated. The detecting level is amplified by an amplifier 32, the amplified level is detected by a signal level detector 33, the height of the generator 30 is set up so that the detecting level of the head 4a is on the position of the center (b) part of the linearly approximated part and the height of both the heads 4a, 4b is adjusted so that a level difference between the detecting levels of both the heads 4a, 4b is included within a prescribed value, so that the level difference of the heads can be set up within a set value.