napos

http://users3.ev1.net/~rpauly/frequently%20asked%20questions.pdf Q. When using the autorouter I get the error “Unreachable SMD Pads …”. What is wrong? A. EAGLE default autorouter grid is set to .05 inches which is very large for SMD components. EAGLE autorouter is grid based so it needs to have a grid intersection at the connecting point of the all pads. To solve this, go to the autorouter/General dialog box and lower the grid. NOTE: Making the grid smaller provides the autorouter with many more options to rout the trace, for then the rout may take more time.

To power LM358N (which consist of two opamps) you have to use command invoke (either on Eagle-s command line or select it from control panel). Then you click on one of the opamps of LM358N and there will be opened a little box where you select the PWR line and click OK. Now there will be your power pins. Now you have to connect these two pins with necessary GND and VDD and you'll see on board layout editor, that the LM358N is connected with the right airwires

Thanks for reply I have one more question, resistor R16 has value 10/1W, this means that the resistor is 10 Ohm and 1W? Update: This was already mentioned in the text, my bad "...LM3915 gets hot so the 10 ohm/1W resistor R16 shares the heat..."

Hello! I have some questions about this circuit: 1)Is IC1 for amplifying the electret mic, because the signal without the IC would be too weak? Can i have a such mic which does not have to have a preamp? 2)Is IC1 supplied with +9(+7,5)V or with +5 V? MC33172P is single supplied, this means that it is amplifying only positive signal (AC can't come out from there)? The AC is not needed because when we want the LED-s to shine, then it is enough from half-sine (pulsating DC)? Is it so? 3)Q1 and Q2 have supply also +9V not +5V? napos