Thanks for the input Colin.
As you become more adept at laying out circuits you will find that your layout is just a jumble.
Place the LEDs near the pins that activate them and always start with the IC socket around the correct way. Place everything as close as possible to the way the circuit is laid out.
The circuit does indeed look jumbled, what you see is my second draft of it, from the brain to the schematic capture software. The reason the IC is facing the wrong way is because the original had everything in a linear fashion flowing from left to right, but it would not fit on the webpage and was a bit unwieldy. I simply folded the circuit and that is how the IC came to be underneath and facing the wrong direction.
Never use a 10 turn pot because you have absolutely no idea where it is positioned and if the value is increasing or decreasing.
The pot comment is well taken. You did not mention what you would have used instead?
The board is absolutely useless without a legend and that is why I have stopped producing my own boards over 40 years ago. This type of board only costs a few dollars to be make with overlay, tinned lands and solder mask by Chinese PCB makers.
When you have 400 projects lying around, like I have, you will appreciate the fact they must be instantly recognisable and usable without any reference to information. Without an overlay you will be frustrated when you come back to it in 6 months, and having produced 20 new projects in the meantime.
I wouldn't say the board is worthless, it has no proven value as of yet, but its certainly not worthless, LOL. But seriously, the board had a legend, I had to wipe it off because the image was mis-transposed. I forgot the mirror image!
I disagree with using the PCB manufacturers for one of's - for hobby and experimentation there is certainly no need to send off a board to be made and wait 2-4 weeks. I would rather get my hands-on locally. I think it would be very disappointing to have waited so long to find out that there was an error in your board and have a dozen worthless boards on hand. I would rather prototype in my backyard, turnaround time is same day!
The regulator does not need a heatsink because it not supplying any current.
Yeah, not getting that at all... Is this based on your experience or some other source of factual data? The voltage regulator will be dropping 4v from the supply times whatever current the circuit will be using. I think the heatsink is a good idea, but I would love to hear your explanation.
The values of the caps where taken from the datasheet. I guess those are considered the minimum values. I have seen what you are referring to when I simulated some of these circuits with Spice. The larger caps create a smoother in/output.