=巻带39-00-0300EOL)Molex43045-1221Molex44914-1003Molex503480-1400Molex52807-0310Molex35745-0110Molex39-00-0302Molex43045-1222Molex44914-1201Molex503480-1600Molex52807-0410Molex35745-0210Molex39-00-0307Molex43045-1223Molex44914-1202Molex503480-2000Molex52807-0610Molex35745-0210Molex39-00-0308Molex43045-1224Molex44914-1601Molex503485-0000Molex52807-0810Molex35745-0310Molex39-00-0339(=卷39-00-0338)Molex43045-1225Molex44914-1603Molex503485-0000Molex52807-0910Molex35745-0410Molex39-00-0342Molex43045-1226Molex44914-2401Molex503500-0991Molex52807-1010Molex35746-0110Molex39-00-0372Molex43045-1400Molex44914-5403Molex50350-9001Molex52808-0470Molex35746-0210Molex39-00-0380Molex43045-1401Molex44914-5803Molex50350-9101Molex52808-0471Molex35746-0210Molex39-00-0428Molex43045-1402Molex44914-6003Molex50351-8000Molex52808-0571Molex35746-0210Molex39-00-0429Molex43045-1406Molex44915-0001Molex50351-8000Molex52808-0670Molex35746-0310Molex39-00-0430Molex43045-1407Molex44915-0011Molex50351-8100Molex52808。声音频率可控,可以做出"多来米发索拉西"的效果。崇明区西门子AD16系列蜂鸣器厂家现货
38770-0305Molex43031-0010Molex44432-0802Molex502386-1270Molex52559-1870Molex35210-0410Molex38770-0306Molex43031-0010Molex44432-2001Molex502386-1470Molex52559-2052Molex35210-1010Molex38770-0314Molex43031-0011Molex44432-2002Molex502386-1570Molex52559-2070Molex35210-1410Molex38770-0320Molex43031-0012Molex44432-2401Molex502426-2010Molex52559-2072Molex35237-1010Molex38770-0406Molex43045-0200Molex44441-1002Molex502426-2610Molex52559-2152Molex35245-4011Molex38770-0503Molex43045-0200Molex44441-2002Molex502426-2610Molex52559-2270Molex35270-0410Molex38770-0528Molex43045-0201Molex44441-2003Molex502426-3010Molex52559-2452Molex35312-0210Molex38770-1103Molex43045-0202Molex44441-2004Molex502426-3010Molex52559-2472Molex35312-0260Molex38770-1105Molex43045-0206Molex44441-2005Molex502426-3210Molex52559-2570Molex35312-0360Molex38770-1912Molex43045-0207Molex44441-2006Molex502426-4010Molex52559-2652Molex35312-0460Molex38770-3306Molex43045-0208Molex44472-0254Molex502426-5010Molex52559-2672Molex35312-0510Mo。崇明区西门子AD16系列蜂鸣器厂家现货蜂鸣器的电路图形符号 蜂鸣器在电路中用字母“H”或“HA”(旧标准用“FM”、“LB”、“JD”等)表示。
将电源(24)脚和④脚排插分别对应插到主板上的插座,通电试机时,电源指示灯时亮时灭,电源风扇和CPU风扇都时转时停,蜂鸣器无通电自检声。测电源各输出脚与地间电压,除紫线与地间电压为稳定的5V,绿线与地间的电压为稳定的,其余各脚与地间的电压都在不停地跳变,说明主板中存在严重的短路故障,拔掉光驱和硬盘的数据线和电源线,通电故障不变。取下CPU和内存条通电,电源风扇时转时停,CPU风扇不转。插入内存条,试短路绿黑线,电源风扇高速旋转,CPU风扇不转,试摸主板各芯片,发现SWSCSOH5514E-NSE0810-A404158S1332860烫手,立即断电。检测数据说明,同一个厂家的不同主板,虽然使用电压相同的电源供电,但其供电脚与地间的正向电阻却相差很多,且供电脚与地间的正反向电阻有时相同,有时相差很大。用测主板各供电脚与地间的正反向电阻查出该主板的短路故障难度很大,只能用测大功率管和各晶体管PN结的正反向电阻来寻求突破。用DT830B数字万用表二极管挡测完主板上的所有晶体管,发现Q55(N790A-EF814)的②脚与③脚间正反向电阻都为4Ω,Q54(N790A-EF814)的②脚与③脚间正反向电阻都为3Ω,Q52(748T40N03G)的②脚与③脚间正向电阻为llΩ,反向电阻为12Ω。
振荡控制电路的第三电感l3的波形以及跟随第三电感l3的波形变化而变化的第二开关管q2、第三开关管q3的波形,其中,第二开关管q2和第三开关管q3的波形为正导通,波形为0截止。由于电感l1的端和第三电感l3的端互为异名端,第二电感l2的端和第三电感l3的端互为同名端,所以第三电感l3的波形与第二电感l2、电感l1同频率,与第二电感l2同相位,与电感l1反相位。当第三电感l3处于正弦波的正半周时,第三开关管q3导通,第二开关管q2截止;当第三电感l3处于正弦波的负半周时,第三开关q3截止,第二开关管q2导通。通过第三电感l3同频率地控制第二开关管q2和第三开关q3的导通和截止,第三电感l3有效的反馈了由电容c1、电感l1和第二电感l2组成的振荡回路,形成了稳定的闭环控制,使工作时的振荡波形稳定。第二开关管q2和第三开关管q3在第三电感l3控制下交替导通与截止,第二开关管q2和第三开关管q3的状态变化,会同频率引起振荡回路的改变。当第三开关管q3导通且第二开关管q2截止时,形成以“第二电感l2和电容c1串联,再与电感l1并联”的振荡回路,如图5所示;当第三开关管q3截止且第二开关管q2导通时,形成以“电感l1和电容c1串联,再与第二电感l2并联”的振荡回路。有“TH”标志的能在湿热带环境下工作。 防护等级:IP20。
这三个晶体管都有被击穿的嫌疑。用热风枪吹下这三个晶体管测量其两个结之间的正反向电阻又符合PN结的单向导电性,击穿漏电现象消失。测这三个晶体管在主板上的焊接脚位②脚和③脚间的正反向电阻仍表现为击穿特征,说明这三个晶体管是完好的,短路问题仍在主板上与这三个晶体管②、③脚相关的其他元件或电路上。测主板上的所有电解电容,发现CPU周围的C609-C612、C615~C617的正反向电阻都为5Ω,试取下CPU时,其正向电阻充电至无穷大,反向电阻为505Ω。用放大镜仔细观察,发现CPU插座内一脚的两个铜触片严重变形,紧紧地绞合在一起,通过放大镜观察,用镊子细心地分离开已经绞合在一起的铜触片,并校正好,安上CPU时,这些电容两极间的正反向电阻又都变为5Ω。是CPU内部击穿了吗?设法购回一个DELL厂原装的同型号新主板,测其电源各输入脚与地间的正反向电阻与坏主板比较,看来问题就出在、电源开关机控制绿线和灰线与地间有元件击穿或漏电。测新板Q55的②脚与③脚间正向电阻为615Ω,反向电阻为672Ω,Q54的②脚与③脚间正向电阻为887Ω,反向电阻为1049Ω,Q52的②脚与③脚间的正向电阻为22Ω,反向电阻为24Ω。 如果给预直流信号蜂鸣器是不响应的,因为磁路恒定,钼片不能振动发音。崇明区西门子AD16系列蜂鸣器厂家现货
AD16-16系列蜂鸣器寿命长,耗能低,体积小,重量轻,可靠性好,造型美观和制造精巧,声音清脆警醒。崇明区西门子AD16系列蜂鸣器厂家现货
散/无料带=卷39-00-0083RS有货)Molex43045-0812Molex44764-1003Molex502790-4091Molex52745-1197Molex35507-0700Molex39-00-0089Molex43045-0813Molex44764-1201Molex502790-5091Molex52745-1296Molex35507-0800Molex39-00-0090Molex43045-0814Molex44764-1202Molex502790-6091Molex52745-1296Molex35507-0800Molex39-00-0095Molex43045-0815Molex44764-1401Molex502790-6491Molex52745-1297Molex35507-0900Molex39-00-0096Molex43045-0816Molex44764-1402Molex502790-8091Molex52745-1397Molex35507-1000Molex39-00-0120Molex43045-0818Molex44764-1601Molex50-29-1031Molex52745-1496Molex35507-1000Molex39-00-0121Molex43045-0819Molex44764-1602Molex50-29-1061Molex52745-1497Molex35507-1100Molex39-00-0123Molex43045-0820Molex44764-1802Molex50-29-1409Molex52745-1597Molex35507-1200Molex39-00-0125Molex43045-0821Molex44764-2401Molex50-29-1608Molex52745-1696Molex35507-1300Molex39-00-0126Molex43045-0822Molex44764-2402Molex50-29-1649Molex52745-1697Molex35507-1400Molex39-00-0127Molex43045-0823Molex44764-2403Molex50-29-1758Molex52745-1797Mol。崇明区西门子AD16系列蜂鸣器厂家现货
=巻带39-00-0300EOL)Molex43045-1221Molex44914-1003Molex503480-1400Molex52807-0310Molex35745-0110Molex39-00-0302Molex43045-1222Molex44914-1201Molex503480-1600Molex52807-0410Molex35745-0210Molex39-00-0307Molex43045-1223Molex44914-1202Molex503480-2000Molex52807-0610Molex35745-0210Molex39-00-0308Molex4...