JPH0188576U - - Google Patents
Info
- Publication number
- JPH0188576U JPH0188576U JP1987184727U JP18472787U JPH0188576U JP H0188576 U JPH0188576 U JP H0188576U JP 1987184727 U JP1987184727 U JP 1987184727U JP 18472787 U JP18472787 U JP 18472787U JP H0188576 U JPH0188576 U JP H0188576U
- Authority
- JP
- Japan
- Prior art keywords
- signal
- output
- preamplifier
- optical
- detection device
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000003287 optical effect Effects 0.000 claims description 7
- 238000001514 detection method Methods 0.000 claims description 4
- 230000008054 signal transmission Effects 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 2
Landscapes
- Television Receiver Circuits (AREA)
Description
第１図はこの考案の一実施例によるアナログビ
デオ信号伝送用光受信キードＡＧＣ回路ブロツク
図、第２図は従来のアナログビデオ信号伝送用光
受信キードＡＣＣ回路ブロツク図を示す。
図において、１は受光素子、２は前置増幅器、
３は可変利得増幅器、４はキードＡＧＣ回路、５
は出力端子、６は電源入力検出タイマ、７はビデ
オ信号出力線、８は信号切換え制御信号出力線、
９は信号切換え装置。なお、図中、同一符号は同
一、又は相当部分を示す。
FIG. 1 is a block diagram of an optical receiving keyed AGC circuit for transmitting analog video signals according to an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional optical receiving keyed ACC circuit for transmitting analog video signals. In the figure, 1 is a light receiving element, 2 is a preamplifier,
3 is a variable gain amplifier, 4 is a keyed AGC circuit, 5
is an output terminal, 6 is a power input detection timer, 7 is a video signal output line, 8 is a signal switching control signal output line,
9 is a signal switching device. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.
Claims (1)
前記受光素子の出力信号を増幅する前置増幅器と
前記前置増幅器の出力信号を増幅する可変利得増
幅器と、前記可変利得増幅器の出力信号により可
変利得増幅器の利得を制御するキードＡＧＣ回路
と、前記前置増幅器出力信号が検出されない場合
一定ビデオ信号を出力する光信号断検出装置と、
前記可変利得増幅器と前記光信号断検出装置出力
を前記光信号断検出装置出力切換え信号により切
換える信号切換え装置とを備えたことを特徴とす
るアナログビデオ信号伝送用光受信キードＡＧＣ
回路。 a light receiving element that receives an optical signal and converts it into an electrical signal; a preamplifier that amplifies the output signal of the light receiving element; a variable gain amplifier that amplifies the output signal of the preamplifier; a keyed AGC circuit for controlling the gain of a gain amplifier; and an optical signal disconnection detection device for outputting a constant video signal when the preamplifier output signal is not detected.
An optical receiving keyed AGC for analog video signal transmission, comprising the variable gain amplifier and a signal switching device that switches the output of the optical signal disconnection detection device using the optical signal disconnection detection device output switching signal.
circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1987184727U JPH0188576U (en) | 1987-12-03 | 1987-12-03 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1987184727U JPH0188576U (en) | 1987-12-03 | 1987-12-03 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0188576U true JPH0188576U (en) | 1989-06-12 |
Family
ID=31476068
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1987184727U Pending JPH0188576U (en) | 1987-12-03 | 1987-12-03 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0188576U (en) |
-
1987
- 1987-12-03 JP JP1987184727U patent/JPH0188576U/ja active Pending