Abstract Data bits represented by magnetic flux reversals at substantially each one-half cycle of uniform data periods are recorded on each of a plurality of data channels of the magnetic tape which is to be tested for dropout and noise characteristics. The recorded data bits on each of the plurality of data channels are then detected by a suitable means such as a read-write head. The detected data bits for each channel are connected as the input to a bistable means which in turn provides one of the inputs to an associated sampling gate employed for the purpose of detecting each dropout of a data bit for each channel. All channels are connected in common to an appropriate means for generating a timing signal in response to the first received output signal from the detected data bits. The timing signal is used to develop a first delay of less than one-half of the data period of the originally recorded data and applied to the sampling gates as their second input, actuating each noninhibited sampling gate to produce a dropout error signal. The timing signal also is used to develop a second delayed signal which is connected to reset the bistable means after the sampling has been completed. Digital counter means are connected to receive and count the dropout error signals thus developed by all the channels. In a preferred embodiment an appropriate chart recorder may also be connected to receive and record the dropout error signals relative to time distribution. Additionally, a digital counter and chart recorder may be connected in each channel to count dropout error signals within each channel and also record error time distribution over the length of tape being tested.
Inventors
👤 F Young
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-10-27 04:03
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/12; G01R33/1207
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
292 words
A system for selectively detecting dropout and noise on magnetic tape comprising: means for recording data bits represented by magnetic flux reversals at substantially each one-half cycle of uniform data periods on each of a plurality of data channels of said magnetic tape; means for detecting the recorded data bits on each of said plurality of data channels and producing output signals responsive thereto; a bistable means associated with each of said plurality of data channels and each connected to a respective sampling gate, each said bistable means being responsive to each output signal of its respectively associated channel for inhibiting the sampling gate to which it is connected; means connected to receive the output signals of all channels and responsive to the first received such signal for producing a timing signal; first delay means responsive to said timing signal for producing a sampling signal delayed by less than one-half of said data period and simultaneously applied to said sampling gates, actuating each non-inhibited sampling gate for producing an error signal; second delay means responsive to said timing signal for producing a delayed re-set signal connected to clear each said bistable means after said sampling has been completed; and means connected to receive and count said error signals; said system being adaptable for detecting noise or non-recorded channels of said magnetic tape wherein said means for recording is disabled and at least one additional channel is recorded with repetitive clock sampling signals and including; switch means operative for disconnecting the sampling gate in the channel having recorded repetitive clock sampling signals and for causing said bistable means associated with each said non-recorded channel to enable its respective sampling gate upon the detection of a noise signal of predetermined amplitude in the channel.
Claim 2
Independent Claim
292 words
A system for selectively detecting dropout and noise on magnetic tape comprising: means for recording data bits represented by magnetic flux reversals at substantially each one-half cycle of uniform data periods on each of a plurality of data channels of said magnetic tape; means for detecting the recorded data bits on each of said plurality of data channels and producing output signals responsive thereto; a bistable means associated with each of said plurality of data channels and each connected to a respective sampling gate, each said bistable means being responsive to each output signal of its respectively associated channel for inhibiting the sampling gate to which it is connected; means connected to receive the output signals of all channels and responsive to the first received such signal for producing a timing signal; first delay means responsive to said timing signal for producing a sampling signal delayed by less than one-half of said data period and simultaneously applied to said sampling gates, actuating each non-inhibited sampling gate for producing an error signal; second delay means responsive to said timing signal for producing a delayed re-set signal connected to clear each said bistable means after said sampling has been completed; and means connected to receive and count said error signals; said system being adaptable for detecting noise or non-recorded channels of said magnetic tape wherein said means for recording is disabled and at least one additional channel is recorded with repetitive clock sampling signals and including; switch means operative for disconnecting the sampling gate in the channel having recorded repetitive clock sampling signals and for causing said bistable means associated with each said non-recorded channel to enable its respective sampling gate upon the detection of a noise signal of predetermined amplitude in the channel.
Claim 3
Dependent Claim
32 words
A system for detecting dropout and noise on magnetic tape as claimed in claim 1 and including means responsive to said error signals for recording the detected errors relative to time distribution.
Claim 4
Dependent Claim
22 words
A system for detecting dropout and noise on magnetic tape as claimed in claim 1 wherein said data comprises digital, return-to-bias bits.
Claim 5
Dependent Claim
29 words
A system for detecting dropout and noise on magnetic tape as claimed in claim 3 wherein said output signals are developed from each negative-going signal of the recorded data.