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I was looking at the schematic of an old HP power supply I bought. It can be found here, around page 60-61.

This schematic was drawn long before CAD was a tool used by engineers. Things were still drawn by hand. I was wondering how drawing large schematics took place. Today, we are used to our fancy EDA tools that will have a lot of nice features to make good schematics. Alternatively, schematics for documentation are sometimes drawn in vector graphics programs like Inkscape or Illustrator, because they can give neater results.

In our CAD packages we have nice auto-annotation, it builds us a nice BoM if we set it up right, and often they even allow us to extract SPICE netlists for simulation, and a whole heap of other information about design and electrical rules. If we discover that moving this component here makes our schematic more clear, we just drag-and-drop - no need to redraw the entire thing!

The old schematics I see always have nice consistent symbols - not what you would expect from hand-drawn schematics. Did they use stencils to always have exactly the same transistor, resistor, capacitor, etc. symbol? Or were those symbols defined in their dimensions and just drawn and measured out every time again? Do they maybe have little pieces of paper with each symbol drawn out on it, and then just move those around to make the schematic without having to start from scratch every time (I'm thinking about those old IKEA desk-papers where you got little cutouts of their desks and you could lay them out to try out layouts in your office)?

I'm aware this is somewhat of an open-ended question, but I'm curious how things were before we had OrCAD, Virtuoso and Altium.

I was looking at the schematic of an old HP power supply I bought. It can be found here, around page 60-61.

This schematic was drawn long before CAD was a tool used by engineers. Things were still drawn by hand. I was wondering how drawing large schematics took place. Today, we are used to our fancy EDA tools that will have a lot of nice features to make good schematics. Alternatively, schematics for documentation are sometimes drawn in vector graphics programs like Inkscape or Illustrator, because they can give neater results.

In our CAD packages we have nice auto-annotation, it builds us a nice BoM if we set it up right, and often they even allow us to extract SPICE netlists for simulation, and a whole heap of other information about design and electrical rules. If we discover that moving this component here makes our schematic more clear, we just drag-and-drop - no need to redraw the entire thing!

The old schematics I see always have nice consistent symbols - not what you would expect from hand-drawn schematics. Did they use stencils to always have exactly the same transistor, resistor, capacitor, etc. symbol? Or were those symbols defined in their dimensions and just drawn and measured out every time again? Do they maybe have little pieces of paper with each symbol drawn out on it, and then just move those around to make the schematic without having to start from scratch every time (I'm thinking about those old IKEA desk-papers where you got little cutouts of their desks and you could lay them out to try out layouts in your office)?

I'm aware this is somewhat of an open-ended question, but I'm curious how things were before we had OrCAD, Virtuoso, KiCAD and Altium.

I was looking at the schematic of an old HP power supply I bought. It can be found here, around page 60.

This schematic was drawn long before CAD was a tool used by engineers. Things were still drawn by hand. I was wondering how drawing large schematics took place. Today, we are used to our fancy EDA tools that will have a lot of nice features to make good schematics. Alternatively, schematics for documentation are sometimes drawn in vector graphics programs like Inkscape or Illustrator, because they can give neater results.

In our CAD packages we have nice auto-annotation, it builds us a nice BoM if we set it up right, and often they even allow us to extract SPICE netlists for simulation, and a whole heap of other information about design and electrical rules. If we discover that moving this component here makes our schematic more clear, we just drag-and-drop - no need to redraw the entire thing!

The old schematics I see always have nice consistent symbols - not what you would expect from hand-drawn schematics. Did they use stencils to always have exactly the same transistor, resistor, capacitor, etc. symbol? Or were those symbols defined in their dimensions and just drawn and measured out every time again? Do they maybe have little pieces of paper with each symbol drawn out on it, and then just move those around to make the schematic without having to start from scratch every time (I'm thinking about those old IKEA desk-papers where you got little cutouts of their desks and you could lay them out to try out layouts in your office)?

I'm aware this is somewhat of an open-ended question, but I'm curious how things were before we had OrCAD, Virtuoso and Altium.

I was looking at the schematic of an old HP power supply I bought. It can be found here, around page 60-61.

This schematic was drawn long before CAD was a tool used by engineers. Things were still drawn by hand. I was wondering how drawing large schematics took place. Today, we are used to our fancy EDA tools that will have a lot of nice features to make good schematics. Alternatively, schematics for documentation are sometimes drawn in vector graphics programs like Inkscape or Illustrator, because they can give neater results.

In our CAD packages we have nice auto-annotation, it builds us a nice BoM if we set it up right, and often they even allow us to extract SPICE netlists for simulation, and a whole heap of other information about design and electrical rules. If we discover that moving this component here makes our schematic more clear, we just drag-and-drop - no need to redraw the entire thing!

The old schematics I see always have nice consistent symbols - not what you would expect from hand-drawn schematics. Did they use stencils to always have exactly the same transistor, resistor, capacitor, etc. symbol? Or were those symbols defined in their dimensions and just drawn and measured out every time again? Do they maybe have little pieces of paper with each symbol drawn out on it, and then just move those around to make the schematic without having to start from scratch every time (I'm thinking about those old IKEA desk-papers where you got little cutouts of their desks and you could lay them out to try out layouts in your office)?

I'm aware this is somewhat of an open-ended question, but I'm curious how things were before we had OrCAD, Virtuoso and Altium.

I was looking at the schematic of an old HP power supply I bought. It can be found here, around page 60.

This schematic was drawn long before CAD was a tool used by engineers. Things were still drawn by hand. I was wondering how drawing large schematics took place. Today, we are used to our fancy EDA tools that will have a lot of nice features to make good schematics. Alternatively, schematics for documentation are sometimes drawn in vector graphics programs like Inkscape or Illustrator, because they can give neater results.

In our CAD packages we have nice auto-annotation, it builds us a nice BoM if we set it up right, and often they even allow us to extract SPICE netlists for simulation, and a whole heap of other information about design and electrical rules. If we discover that moving this component here makes our schematic more clear, we just drag-and-drop - no need to redraw the entire thing!

The old schematics I see always have nice consistent symbols - not what you would expect from hand-drawn schematics. Did they use stencils to always have exactly the same transistor, resistor, capacitor, etc. symbol? Or were those symbols defined in their dimensions and just drawn and measured out every time again? Do they maybe have little pieces of paper with each symbol drawn out on it, and then just move those around to make the schematic without having to start from scratch every time (I'm thinking about those old IKEA desk-papers where you got little cutouts of their desks and you could lay them out to try out layouts in your office)?

I'm aware this is somewhat of an open-ended question, but I'm curious how things were before we had OrCAD, Virtuoso and Altium.

I was looking at the schematic of an old HP power supply I bought. It can be found here, around page 60.

This schematic was drawn long before CAD was a tool used by engineers. Things were still drawn by hand. I was wondering how drawing large schematics took place. Today, we are used to our fancy EDA tools that will have a lot of nice features to make good schematics. Alternatively, schematics for documentation are sometimes drawn in vector graphics programs like Inkscape or Illustrator, because they can give neater results.

In our CAD packages we have nice auto-annotation, it builds us a nice BoM if we set it up right, and often they even allow us to extract SPICE netlists for simulation, and a whole heap of other information about design and electrical rules. If we discover that moving this component here makes our schematic more clear, we just drag-and-drop - no need to redraw the entire thing!

The old schematics I see always have nice consistent symbols - not what you would expect from hand-drawn schematics. Did they use stencils to always have exactly the same transistor, resistor, capacitor, etc. symbol? Or were those symbols defined in their dimensions and just drawn and measured out every time again? Do they maybe have little pieces of paper with each symbol drawn out on it, and then just move those around to make the schematic without having to start from scratch every time (I'm thinking about those old IKEA desk-papers where you got little cutouts of their desks and you could lay them out to try out layouts in your office)?

I'm aware this is somewhat of an open-ended question, but I'm curious how things were before we had OrCAD, Virtuoso and Altium.