ECG原理与技术

1、 心脏是人体血液循环的动力装置，心脏自律不断地心脏是人体血液循环的动力装置，心脏自律不断地进行有节奏的收缩和舒张活动，使血液在闭锁的循环系进行有节奏的收缩和舒张活动，使血液在闭锁的循环系统中不停的流动，使生命得以维持统中不停的流动，使生命得以维持。 心肌细胞的除极、复极过程和动作电位心肌细心肌细胞的除极、复极过程和动作电位心肌细胞在兴奋时所发生的电位变化称为动作电位，即心胞在兴奋时所发生的电位变化称为动作电位，即心肌细胞的除极和复极过程（如图）。肌细胞的除极和复极过程（如图）。旧式的心电图机多数采用热笔在热敏纸上记录波形,存在着打印效率低、噪声大、波形失真等缺点;而热敏打印机的热敏头是由一排体

2、积很小( 8个/mm)的加热单元组成的,每个加热单元加热时与之相接触的热敏纸的对应位置将会变黑,通过控制各个加热器件的加热与否即可控制每一行的打印内容,再由步进电机控制走纸换行,从而在热敏纸上绘制出各种图形。由于热敏打印机具备体积小、重量轻、可靠性高、打印字符清晰、噪声小、走纸均匀等特点,因此成为新型心电图机的首选金属反应金属反应电极电位电极电位(V)(V)Zn Zn2+ +2e 0.763Ni Ni2+ +2e0.250Cu Cu2+2e0.337Ag Ag + e0.799AgCl+e0.22312SLTM金标准分析程序 屏幕3通道显示，12导可同步打印 自动，手动，心率失常模式 内置欧洲

3、标准的HEART分析软件QTD的精确分析 报告准确，格式多样 交直流两用 可升级运动测试系统 抗漂移系统(ADS)及自动基线调整 主要规格： 导联：标准12导联 增益转换：5，10，20，40mV，手动或自动 记录纸：GE marquette-hellige式对比度热敏纸300*210mm电源：交流电源：85-264V,直流电源：内置电池 外形尺寸：370*320*95（mm） 重量：5.6Kg（含电池组）Device cannot be switched on even though power plug is plugged in- green power lamp LED is off

4、and device cannot be switched on:- Power cable defective or not plugged in correctly?- Primary fuses in the mains input module defective?- Connector from the mains input module to the mains switching power supplyplugged in correctly, or cable defective?- Connector from the mains switching power supp

5、ly to connector POSUP/ on thePCB Control plugged in correctly, or cable defective?- Keypad via connector KEYB/ on PCB Control plugged in correctly?- 26,5V on the connector POSUP? if no: - mains switching power supply defective if yes: - PCB Control defective- or keypad defective- green power lamp LE

6、D is on, but device still cannot be switched on: - PCB Control defective- or keypad defectiveDevice cannot be switched on when being battery-operated only- Is the battery depleted?- Plug in power plug, green power lamp LED should glow and the device can beactivated, if not: - refer to Device cannot

7、be switched on even though powerplug is plugged in”.- By connecting the power plug, rapid charging is activated, LED1 on the PCBBattery Charge is activated if not: - PCB Battery Charge is defective- With power plug plugged in, let unit charge for 10 minutes, then disconnectpower plug. Can the device

8、 be switched on and can a recording be started? if yes: - Function OK., continue loading with plugged mains plug if not: - Battery disconnected or cable defective?- Battery defective (no capacity)?- PCB Battery Charge defective ( Si1?)?No display on the screen- Does the yellow Stop LED on the keypad

9、 glow after the device is switched on? if not: - refer to Device cannot be switched on .” if yes: - continue- Does a beep sound approx. 10s after switching on the MAC1200 occur (indicatesthe successful power up self-test)? if not: - Self test error, PCB Control defective if yes: - continue- Contrast

10、 badly adjusted?- Can the background illumination be activated by pressing a key?- Can the display test in Section 3.3 be applied successfully? if not: - graphics display module defective- or PCB Control defectiveMAC 1200 fails to give printout, no paper transportPerform the following test in the 6-

11、lead operating mode:- Paper available? Paper correctly inserted? Paper transport problems (jam)?- Paper feed flap correctly engaged on both sides?- After pressing the start key, the green start Led must glow if not : - keypad defective? Apply keypad test in Section 3.4 if yes: - continue- Paper feed

12、 flap correctly engaged on both sides?- Mark reader defective or not plugged in?- All connections for printhead and Motor are plugged in?- Motor blocked ? (check roller, transmission)- Operating only on battery which is strongly depleted? if yes: - plug in power plug if not: - PCB Control defectiveP

13、aper transport functions, no printout- Paper feed flap correctly engaged on both sides?- All connectors for printhead plugged in?- Operation with strongly depleted battery? if yes: - plug in power plug if no: - PCB Control defective- or printhead defectiveMAC 1200 prints, but only baselines are printed out- Electrodes applied correctly?- Electrode cables pl