digirailmodel

In model railroad application, the power is from the rails, the contact between wheel and rail is important. If the contact is not always solid, the power may be opened, then LED will be turned off or blinks and model stops to move. The capacitor is a component which has the ability or “capacity” to … Read more

As the figure (figure from internet), the portion of left-upper side is for resistance measurement.The value of each mode indicate the maximal measurable resistance. In case that the multimeter displays OL, it means overloaded, so just try a higher mode for correct measurement.In the mode of 2K (along with a diode symbol), user can use … Read more

A resistor is a component that resists the flow of electricity. With the same terminal voltage across resistor, the larger resistance, the lower current flow. There are DIP type resistor and SMD type resistor (figure from internet). The larger body size of the same resistance, the higher power rating. The popular power rating of DIP … Read more

LED has two terminals: the anode (labeled with plus-sign (+)) and the cathode (labeled with minus -sign (-)). For correct operation, an LED only light when voltage is applied in the forward direction of the diode. Simple LED circuit with resistor for current limiting The current in an LED rises exponentially with the applied voltage, … Read more

Connect IN1/IN2 of HA24100 DCC coach light to FD100 decoder. Please refer to FD100 user manual for details. Connect and solder the RED and BLACK wire of FD100 to the contact of pickups. IC2000 is a double-deck passenger carriage (coach), two HA24100s are installed for independent light effect in each deck. First, Put and fasten … Read more

There are no pickups in this coach, prepare two pieces of thin coopers for one bogie according to the distance between wheels and size of bogie. One cooper is placed across the wheel axles and the other cooper circle around the bogie and weld with the first cooper together for fixing. Please pay attention in … Read more

Unpack and take out the model, WOW, model with beautiful appearance. Release the roof from the coach body carefully. After the roof come off,you can find several compartments in this coach and several couchettes in each compartment. First, prepare two wires for connecting drM light bar to rail power. Please note that the wire shall … Read more

在鐵道模型中是靠輪子接觸軌道通電,所以在行走中常常會出現輪子接觸不好的情形,所以會出現燈光閃爍或是行走停頓的情形. 電容是儲存電力的元件,所以當接觸不良發生時,就需要電容來補足晶片電力,不會讓晶片失去功能. 電容的單位是法拉(F),所以可以看到晶片會寫外掛電容100uF~2200uF(u = 0.000001),電容越大,晶片可以支撐接觸不良的時間也越久,不過電容越大也會出現尺寸變大的情形. 電容的種類有很多種形式,貼片電容,鉭電容,電解電容,法拉電容….,有些電容有分極性,有些沒有,晶片使用的都是指電解電容. 電解電容是有極性與耐壓值,鐵道模型HO大約在18V以下,所以電容耐壓值需要25V以上,極性長腳為正端,不要接反,不然電容有可能損壞. 法拉電容是有極性與電解電容類似,不過電壓直都很低大多是2.7V,3.3V,5.5V耐電壓值,使用上需要注意,除非晶片有支援.

上圖(圖片取自網路)是三用電表檔位分別是左上角藍色量測電阻值,不同的電阻值代表那個檔位可以測量的最大值,超過需要切換下一個檔位,在2K檔位有一個二極體符號,這個可以量測二極體與發光二極體(LED),量測LED時LED亮起,紅色探棒代表LED正端,黑色探棒代表LED負端.反向LED不會亮. 右上角紅色為AC電源量測,通常量測家裡AC110V或是220V,量測 DCC是不準的,電表的設計是量測標準AC電源. 右側黑色部分是量測直流電源,像是量測電池或是鐵道模型電源控制器(非DCC)電壓值. 右下角綠色區域量測電流大小. 左下角黑色量測電晶體

電阻功能就是阻止電流,會因為電阻值大小使得電流產生大小變化. 電阻有分成插件式(DIP)與表面黏著(SMD)兩種(圖片取自網路),同樣電阻值,電阻體積大小不同分別代表電阻可以容許的功率大小DIP分為1/8W,1/4W,1/2W,1W,…..,SMD分為0201,0402,0603,0805,1206,1210……. 電流大小與電壓高低與電阻大小有關,公式可以計算相對關係 I(電流)=V(電壓) / R(電阻值) 單位 K代表1000 ,m代表0.001 1K電阻= 1 x 1000 範例: 電壓10V,電阻值1K I = 10 / 1000 I=0.01A I = 10mA.