Hi!
I'm working on a circuit using a GENIE E18 to pulse a 4026B and get a count. The problem is the clock does not seem to be registering the pulse. I've run the signal through a TIP121 transistor. Could this be the problem? I've done this a million times with a 555 and it's been fine. Could it be something to do with the PIC signal itself? I've checked the 4026B spec but I'm no more enlightened.
It's working fine in simulation using Circuit Wizard.
Any help greatly appreciated.
Thanks

 

Use a 2n2222a but really need to see your circuit.

 

The ULN2803 is an open-collector driver. To assert a valid logic 1 a pullup resistor is required (i.e. a resistor of perhaps 10 k, value not too critical here, between the output and V+). I don't understand what the TIP121 is for - that's a power transistor.

 

Where did you see a ULN2803 he's using the tip-121 He don't need it but without seeing who knows.

 

I found a schematic of a Genie E18 project board that has a 2083. Perhaps that is not the board in use. More info required.

 

I seen that too cant figure why hes using a tip 121 to clock a 7 sig driver

 

Thanks for the advice. Was recommended the TIP121 but now see the issue. I actually have a ULN2803 in the circuit for some relays that the GENIE is also driving so that will work well. I’ll let you know how I get on.
Thanks again!