Wheel of FORTUNE HELP

[garage100]

The above circuit was built on a matrix without transistors ( 2n3904 ) .
The Circuit worked fine until the transition to the solder board which included all the parts. I checked the board three times .
The Circuit is taken from http://www.talkingelectronics.com/EM/KitsForSale/WheelOfFortune.html
I wanted to restrict the movement of four LEDs , so I shorted leg 10 to 15 in 4017 .
In addition I wanted to control the timing and changed the capacitor connected to 555 to 100U and added variable resistors.
The problems :
1. After switching to a solder board the rotation stopped at the same group of LEDs repeatedly. the randomality has disappeared . Is there a mistake in a circuit attached ? Why doesn't it stops with a another group of leds in every rotation round?
2 . The LEDs are piranha 5 mm 3v . When the group of blue LEDs turn on, the LED connected to the resistor(150) is flashing. Is the LED broken or is there a problem in 2n3904 ?

I'm really desperate
please help
yoav

 

[Colin Mitchell]

You can't connected LEDs in series without a resistor

 

[KrisBlueNZ]

Your schematic is pretty short on information. What's the battery voltage? And every component should have a circuit reference so we can identify it when we're talking about it.

Each of the four transistors drives a pair of LEDs in series, which have no current limiting resistor. As Colin says, you can't normally do that; the effect depends on the battery voltage and type, but is not likely to be good.

This could be the reason why it always stops on the same group of LEDs.

The red LED could be flashing because you accidentally used a flashing LED instead of a normal LED. Flashing LEDs are available; there is a little circuit inside them to make them flash.

Your preset variable resistors are drawn wrong; if you only connect to the two ends, the resistance will be constant. You need to connect the wiper to one end.

Edit: And welcome to Electronics Point!