When doing computer-aided design for electronic printed circuit board production, it is extremely important that the schematic capture process be
exactly reflected in the netlist used to produce the board layout. And vice versa, so if any manual changes in routing are made, those changes are immediately propagated backwards into the schematic. A good PCB software design package will go a long way toward ensuring the process from schematic capture to component placement to routing is done correctly. BTW, the routing on your PCB really sucks.
What software did your "professionally produced" circuit board designer use? Was a printed schematic made and compared to the schematic you used to produce the breadboard prototype? What design rules were established, followed, and checked before the board was fabricated?
The devil is in the details when going from the virtual computer-designed and simulated world to the real components world. Simple things, like forgetting (or not knowing) to include bypass capacitors at the power pins of
every integrated circuit can quickly torpedo a project and make troubleshooting a nightmare. Your
schematic shows several pins of the CD4013 CMOS dual D-type flip-flop unconnected. Although perhaps they are connected to the ground plane of the circuit board, this connection is not documented on the schematic.
It is
verboten to leave unused input pins unconnected or floating on CMOS ICs. ALL unused inputs must be terminated at either Vcc or GND. Please read Section 10 of
this Texas Instruments datasheet. Actually, you should read and understand the entire datasheet.
If you breadboard a circuit from a schematic using a solderless breadboard, and it works properly, then it should also work properly when implemented as a printed circuit board... provided the circuit doesn't depend on uncontrollable things like logic propagation delays, race conditions, stray capacitance and similar anomalies to operate "properly" and fortuitously.
I like bread-boarding prototypes before making a PCB commitment, but I am fully aware of the problems that can (and do) occur: intermittent or unreliable connections, excessive stray capacitance and/or inductance (especially at high frequencies), inability to handle high currents (especially pulsed high currents), and plain old errors of omission and substitution in making point-to-point connections to components.
If you continue with your "hands on" journey learning practical electronics you will discover many more "gotchas" that can waste hours, days, even weeks of your time. Best to write these down in a journal of discovery until they are etched deep into your subconscious, lest you keep on repeating them. My favorite: always make sure electrical power of proper voltage and current capacity is available and applied to your breadboard circuit before assuming anything else is amiss. Don't ask how I spent a whole day at the bench in the previous century learning this particular lesson.
So I am reaching out to all you geniuses here. First of all I am so thankful I was able to find this site because I am at my wits end! The goal of the circuit below is multi faceted.
