# What does this circuit symbol mean? [duplicate]

This question already has an answer here:

I'm a student who is trying to build a wah pedal for a guitar. I came across this diagram for how to wire the circuit (from this site) :

Within the diagram, I am not sure what the following symbol means:

This variant of the symbol also appears in the diagram and I am not sure what to make of it either:

I'd much appreciate if anyone could explain these symbols to me as the only place I have been able to find these online was on this very circuit diagram and no context is provided as to their meaning.

## marked as duplicate by Eugene Sh., Elliot Alderson, Finbarr, JRE, Nick Alexeev♦Jun 18 at 14:47

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

• @EugeneSh. related, I would say but not a duplicate. The linked question is asking what pin is what. This question is asking what is the symbol. That's 2 different questions. – MCG Jun 12 at 14:39
• @MCG The title of that one is the answer to this one, no? So I would say that this question is a subset of the linked one. – Eugene Sh. Jun 12 at 14:40
• @EugeneSh. Subset is not a duplicate. A duplicate to me is someone asking the same question and would receive the same answers. Therefore, it is not a duplicate. It is certainly related though – MCG Jun 12 at 14:42
• @MCG Well, I don't know how SE is defining it. If someone is asking how much is 1+1, then it can be definitely closed as a duplicate of a question asking how much is x+y. Anyway, we don't have to agree on this :) – Eugene Sh. Jun 12 at 14:44
• It's not really a DC ("barrel") jack; given the application this is probably a TS jack, probably the ¼" variety. They have the same symbol, though. – Hearth Jun 12 at 14:46

## 2 Answers

That signifies a jack with a connection that breaks when a plug is inserted. In the case of your schematic, that connection isn't connected to anything anyway, so it shouldn't matter.

• The switch is physically inside the jack. On the schematic it is where the arrowhead touches the line with the kink in it. – evildemonic Jun 12 at 14:36
• It isn't connected to anything, as signified by the 'X' at the other end. – evildemonic Jun 12 at 14:37
• @DarthVader If your question is about where the bypass switch is, it is not shown in that schematic at all. You can see it wired in one of the photos from that link, though. I also have a few of these, that switch is wired to both jacks, shorting them together and cutting out the circuit entirely. – evildemonic Jun 12 at 16:33

Barrel connector with switch -- 2 conductors, 3 contacts.

Here are some similar parts Digi-Key has listed. Most will show a diagram in the data sheet.

Terminal 1 is the sleeve connection, and terminal 2 is the tip. Terminal 4 is a switch contact that is connected to the tip when there is no plug inserted, and disconnected when the plug is inserted.