I am building a smaller version of a seven segment scoreboard that I built last year. The first board that I built is working great but I am having problems getting the second one to work properly. The components that I am using are the same as the first. They consist of a CD4093 Schmitt Trigger, MC14543B Latch Decoder, MC14553 BCD counter, and a ULN 2004 AN IC. driver chip. It is a multiplexed system using two PNP 2907 transistors. with a .001uf cap between the number 3&4 pin on the MC14553 and 10k resistors going to the transistor base. I guess before I get into a whole lot of detail, would anyone have any suggestions as to why the display only shows 2, 4, 6, 8, etc. No odd numbers. I have checked and double checked the circuit many times but cannot find the problem. The score board runs on 12 volts dc and the battery is fully charged.
Thanks in advance for any help I may receive. Lorne
Thanks in advance for any help I may receive. Lorne