JPS6313424U

JPS6313424U -

Info

Publication number: JPS6313424U
Application number: JP10725686U
Authority: JP
Priority date: 1986-07-12
Filing date: 1986-07-12
Publication date: 1988-01-28
Anticipated expiration: 2001-07-12
Also published as: JPH0633544Y2

Description

[Brief explanation of the drawing]

第１図は本考案に係る磁気記録再生装置におけ
る記録速度判別装置の実施例を示すブロツク図、
第２図ａは標準速再生中の半速記録部分とビデオ
ヘツドとの関係を示す図、第２図ｂ〜ｆは半速記
録部分の標準速再生時における回路各部の波形を
示す波形図、第３図ａは半速再生中の標準速記録
部分とビデオヘツドとの関係を示す図、第３図ｂ
〜ｆは標準速記録部分の半速再生時における回路
各部の波形を示す波形図である。１ａ〜１ｄ…ビデオヘツド、２ａ，２ｂ…再生
ヘツド切換スイツチ、４…パルス形成回路、５…
判別手段、５１…第１のリトリガモノマルチバイ
ブレータ、５２…第２のリトリガモノマルチバイ
ブレータ、５３…カウンタ、５４…フリツプフロ
ツプ回路。 FIG. 1 is a block diagram showing an embodiment of a recording speed discriminating device in a magnetic recording/reproducing apparatus according to the present invention;
FIG. 2a is a diagram showing the relationship between the half-speed recorded portion and the video head during standard-speed playback, and FIGS. 2b to 2f are waveform diagrams showing the waveforms of various parts of the circuit during standard-speed playback of the half-speed recorded portion. Figure 3a is a diagram showing the relationship between the standard speed recording portion and the video head during half-speed playback, Figure 3b
-f are waveform diagrams showing waveforms of various parts of the circuit during half-speed playback of a standard-speed recording portion. 1a to 1d...Video head, 2a, 2b...Reproduction head selection switch, 4...Pulse forming circuit, 5...
Discrimination means, 51...first retrigger monomultivibrator, 52...second retrigger monomultivibrator, 53...counter, 54...flip-flop circuit.

Claims

[Scope of utility model registration request]

In an azimuth recording type helical scan type magnetic recording/reproducing device, there is provided a means for creating a detection pulse with a constant period corresponding to a waveform change of a reproduction RF signal during reproduction, and a first means having a time constant shorter than the period of the detection pulse. a retrigger monomultivibrator; a second retrigger monomultivibrator that receives the output of the first retrigger monomultivibrator and has a time constant longer than the period of the detection pulse; A counter that counts the number of outputs of the mono multivibrator, is reset by changing the output of the second retrigger mono multivibrator, and outputs a count-up signal when a predetermined count value is reached, and a counter that outputs a count-up signal by this count-up signal. 1. A recording speed determination device for a magnetic recording/reproducing apparatus, comprising a flip-flop circuit which is inverted when the flip-flop circuit is turned, and the output of the flip-flop circuit is used as a signal for determining a mismatch between the reproduction speed and the recording speed.