RGB circuit/red issue

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Icanmakeit67

Joined Sep 23, 2018
210
I built this circuit. It seems to run fine with the green and blue colors showing up but the red does not show up and the bc557 transistor gets hot. I replaced it but it must be a design flaw because nothing changed. Running at 9v. I believe an accommodation should be built in for the difference in voltage required by each color.
can I get some ideas. Please and Thank YouIMG_0793.png
 

BobTPH

Joined Jun 5, 2013
11,480
Your circuit would be much easier to read with all the transistors flipped top to bottom. We usually put emitter down on NPN and up on PNP so current flows top to bottom.
 

dl324

Joined Mar 30, 2015
18,238
I replaced it but it must be a design flaw because nothing changed.
That circuit is garbage and the schematic is drawn very poorly. The LEDs are wired in parallel with no ballast resistors, there are no current limiting resistors, connection dots are missing, pins on the timer aren't connected, the transistors are drawn upside down, pin function isn't labeled, rectifier diodes are overkill... Do the colored wires mean anything?

You're lucky the 10k resistors likely limited current and prevented all of the LEDs from being burned out. If the 9V supply is a wimpy transistor radio battery, that may have help save things from burning up.
 
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