Michael: GOOD JOB!!! on the KiCAD PCB layout!!! But.....Hi,
Maybe far too late, but I tried to design some API500 gear and if you or anybody is interested you could use the edges in the attachment (KICAD project). For mounting the front panel I simply used these mounting screw holes (therefore you find the strange holes in the PCB): %product-title% kaufen
View attachment 84529View attachment 84530
Worked quite nicely and everything fitted very well. I also attached a pic of the finished build and the PCB itself so you can get an idea.
Maybe it can be of use for you or someone in this forum. Feel free to use it, as long as it is for non-commercial use ...
Brian: Good to hear your story of early PCB designs. Believe it or not.....I -- STILL HAVE -- my "Bishop Graphics" 3-ring binder of PCB "sticky" items and templates. Can you imagine THIS??? >>> I once had to design a 12-layer PCB using the "Bishop Graphics" materials where the PCBs were to be used on U.S. fighter jets!!! If you can remember, there used to be "D-sized" Mylar sheets that had a row of "Alignment Holes" punched along the top-side of the sheet. You used to have this really long metal bar taped down on your drafting table or "light table" that had short "Alignment Posts" on them that were used to align and hold all of your Mylar sheets in one place. I always could never make up my mind if I wanted to use a "Pad Master" sheet or go ahead and put pads down on every layer. Unlike doing PCB designs today, you - REALLY HAD TO THINK - about what you were doing before you did it, or you could kill yourself easily!!!One other thing crossed my mind. Back in Ye Olde Days (1970's) , I designed a few boards which required edge connectors. Hard gold plating on the fingers was a standard requirement to ensure longevity of the fingers through multiple insertions/removals of the card.
I was doing the card designs at 2X size using a mylar sheet with a translucent grid sheet under the mylar for placements, both stacked/taped onto a light table, and I used an Xacto knife and a variety of "stickies" sold by Bishop Graphics.
I now distinctly recall a Bishop "sticky" for edge connectors that had a "plating bar". It added a small trace that extended from the tip of each edge finger out to a trace that ran at a right angle along the width of all the fingers. The PCB fab shop required (?) that in order to do hard gold plating of the fingers. After plating, the PCB shop cut/milled off the excess with the plating bar.
I have no idea what fabrication requirements are in this century. A brief websearch found this:
The pic shows the "pip" from the tip of each finger, and the text mentions "plating bar".
Here's some 500-Series information that you should find to be of some interest!!!Anyone know how I can get the correct board size and card edge for a 500 series module to start with in KiCad? Thanks.
Hi,Michael: GOOD JOB!!! on the KiCAD PCB layout!!! But.....
Now.....Keep in mind that I am only a "beginner" in performing PCB layouts, as I have been designing PCBs for over 40-years, starting with "manual hand-taping" methods as Brian as mentioned using the "Bishop Graphics" materials and using a variety of CAD-programs over the decades at all of the different companies I have worked with within the aerospace/avionics, defense, medical electronics, NASA, R&D laboratories, telecommunications and video electronics industries. So, you can take my comments with "a grain of salt", if you wish, OK???
First off.....while "Copper Pours" are generally a good thing, you don't generally want to have them go out to the edge of the PCB for a variety of reasons. It would be preferable to back-off the "Copper Pour" somewhere in the neighborhood of 50-to-100 mils as a clearance. The same would go for your TOP and BOTTOM soldermasks. Secondly.....when you have a "Copper Pour" on both sides of the PCB as you have done, it helps tremendously to connect each of the "Copper Pours" together using what are called "Stitching Vias". What are "Stitching Vias"? "Stitching Vias" are independent "free-form" vias that are typically connected to the "GROUND" net and are placed by the - dozens - all over the PCB. While the "Plated-Thru Holes" of the capacitors and other components that are connected to "GROUND" will connect both of the "Copper Pours" together, "the more the merrier" principle applies here. Meaning, if you consider the via "hole" as a resistor, then the more resistors that you have connected in parallel, the lower the overall resistance will be and that's a "good thing"!!!
Now, this may not be as an important a parameter in an audio PCB, but it - does - become a critical parameter in all of the "RF" PCBs I have designed. Most of my "RF" PCBs end up having several hundred "Stitching Vias" and on the larger "RF" PCBs I have done, the number can reach into the low thousands!!!
Another item you need to keep a watch out for when doing a "Copper Pour" is inadvertently creating what is called an "Isolated Copper Pour". What that is is a "Copper Pour" area that is -- NOT -- connected to anything and is just a piece of "isolated copper" on the PCB. Usually, the use of "Stitching Vias" can eliminate any "Isolated Copper Pour" areas, but they can also be eliminated by how your "Copper Pour" parameters are setup (i.e., line-weight, spacings, etc.). You may have to dig down into the KiCAD setup parameters to see what may or may not be available to change in this regard.
If you would like to send me your KiCAD PCB file, along with its "Project" file and whatever else it takes for me to load-in your PCB design, I could give your layout a better review and then give you some better pointers on PCB layout for your next project. Another member of this forum recently sent me his GERBER files of an API 2520 module so I could modify and update his GERBER data to be more correct. As it turned out, as I was also reviewing his N/C Drill file, I saw some additional errors within that file and I went ahead and corrected those errors for him. After I had e-mailed his newly-generated GERBER and N/C Drill data files back to him, he placed an order with his PCB shop for 100 PCBs and he recently wrote to me to say that his new boards look GREAT!!! He then mailed me 6 of his new PCBs, which I should receive sometime later on today. (NOTE: I also have a special GERBER and N/C Drill data editing program).
I'm just trying to help out!!!
Hi Brian,Still curious......is a "plating bar" required in the PCB layout for hard gold plating of edge fingers, or can the fabricator figure it out when they see the design?