Won't save junctions in schematic

First attempt at drawing a schematic in KiCad (I usually only have simple PCBs that I draw directly on to the board). When I finally think I have completed the circuit, I ran the “Electrical Rules Check” which reported a number of errors - no real surprise for a first attempt - the software highlights where the errors are (mainly no connection) so I added junctions where the arrows were pointing then ran the check again, only to have the same result. I then added the junctions again and used the “save as” with a different title but even after closing KiCad and then reopening the newly saved file, the junctions are still missing. Some errors are for deliberate “no connection” on a socket and it tells me to “use a ‘no connection flag’ to suppress this error” but where do I find them ?

There is obviously no point in generating a net if there are missing connections. Can anyone help please ?

I would have included the schematic with this post but wasn’t sure how to do so.

It’s the X in the RH toolbar, hotkey Q. Don’t add junctions willy-nilly unless you really intend to connect.

Thanks for that. I can remove some errors with it but it still tells me there are other “no connections” even though I think they are connected. Looks like I’ve found how to upload the schematic.TrainEngineer1d.sch (16.2 KB)

But they are not connected. In many places you have used the bus tool instead of wire.

When a wire is connected to a pin, the circle of the pin and the square end of the wire vanish.

you might be interested in Tutorial: Introduction to PCB design with KiCad version 5.1 (Getting Started)

Ah, thanks @pedro, I used the bus tool for all the power feeds and wires for the signal feeds. A (very old) drawing package I have used in the past didn’t differentiate apart from different colours. Many thanks for your help, I will change the bus feeds to wires and see how I get on.

Have now replaced all of the bus wires with ordinary wires and that has cleared all barring two problems and I cant see why there should be a problem. The ERC still reports no connection to the input of IC1 (pin 8) and the ground of IC1 (pin 7). I have added the changes to the new schematic (attached). I have even added junctions to those points and it still shows errors. TrainEngineer1e.sch (17.0 KB)

Your schematic now is correctly connected, your issue now is with the power flag

this link is an introduction, but if you search in the forum you will find that it is quite a recurring topic.

p.s. in your case the power flag will be after the fuse and not directly at the screw terminal.

hope this helps.

OK, learning all the time and now have no errors reported - magic ! Thank you @der.ule for your help.

I now have another problem. I selected “assign footprint” and I’m presented with a list of components, some have footprints assigned and some don’t. For the first component, I chose the correct footprint from the list on the right, “filtered footprints”, followed by clicking “apply, save schematic & continue”. Nothing changes in the central list. I have even tried closing the program and re-opening it but the footprint is not assigned. One strange thing, when I right click “view footprint” for my selected footprint in “filtered footprints”, the footprint viewer is showing a blank view, yet if I go directly to the layout editor, I can place the same footprint (which is the way I usually make simple PCBs). What am I doing wrong this time ? Don’t know if it will help but this is the corrected schematic : TrainEngineer1g.sch (17.9 KB)

I can’t see the list of the footprints because I use my own libraries.

Anyway, once in the assign footprint list, I would uncheck all filters.
Then, I select the library on the left column for the component I want. For example Resistor_THT for the resistors.
Now, select (highlight) for example R3a1 in the center column and choose
Resistor_THT:R_Axial_DINxxx… footprint on the right column with double-click.

The center column must show the footprint field filled with the name of the chosen footprint. Now, Apply, Save Schematic and continue

You got around to check the link that @Rene_Poschl posted for you before ? Inside you will find a link to this FAQ:

You do have to make “double click” on the footprint on the right side list, you will see that the footprint gets assigned to the selected symbol in the middle list, when you are finish you can do then “apply, save schematic & continue”, it will take the relationships that you just created and "apply* them to the schematic, and save those relationships and the schematic so you can continue making selections or continue drawing your schematic.

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Thanks to you all - I now have an error free net list.
Let’s just see if I can convert it to a working PCB.

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