Schematic heavy questioning (Simple PT2399 delay and Triple Splashback)

[eric]

They are not connected…
C37 C38 C39 and C40 are decoupling caps.

[Alex1]

@analogoutput

This is a Eurorack style 10 pin power header:

And this:

connects wherever you see +12V marked, for instance here:

it’s providing power to a 5 volt voltage regulator (L7805), which is where the +5 V comes from.

(Not all modulars use ±12 V, ±15 V is rather common, but Eurorack and Kosmo use ±12 V; the Eurorack specification actually calls for +5 V to be supplied too, but usually Eurorack systems just distribute ±12 V and if +5 V is needed it’s done in the module with a regulator, like this.)

This:

tells you +12 V should be connected to pin 4 of the TL074, and -12 V to pin 11.

Here

you see +5 V (from the L7805) is to connect to pin 1 on the PT2399.

I think that’s it for the power distribution.

Except that there really should be some capacitors added to this circuit. Two 10 µF electrolytics, one from +12 V to ground and one from -12 V to ground, both located close to the power header, and three 100 nF ceramics, from +5 V to ground near pin 1 on the PT2399 and from +12 V and -12 V to ground near pins 4 and 11 on the TL072. Ideally they should be located right next to those pins. These are bypass capacitors and while the circuit will probably work okay without them, it’s best to add them.

And from @analogoutput Maybe I still got it wrong haha

[analogoutput]

Nowhere in there did I say to connect +12 V to -12 V.

[analogoutput]

Sorry, error on my part. Picture should have been

(Fixed error in above post)

[Alex1]

ok ! no problem I’m glad it’s clarified now !

[THOGRE]

Don’t worry, I started DIY about a year ago and actually build everything according to the stripboard layout. I always have a schematic next to it, but only with this I can’t build something on a strip board. At least nothing bigger. The delay would be too big for me again. Confuses me and only chaos comes out.
But at some point I can do it too!

Simply dont give up !

Greetings THOGRE

[Alex1]

Hey thanks ! only chaos haha

[Alex1]

Hi again,

I have 4 questions, related to the previous schematic. I numbered my questions to fit in with the reference picture I sent below So,

1- Are those 2x4 headers ? is one male and the other female ?

2- I can’t find any component in EasyEDA that looks like a jack input. What do I do ? And I want 2.5mm jacks. Is it ok if I just replace the 1/4 jack for some 2.5mm ? Do I have to modify the circuit ? (This one was 2 questions in one)

3- What’s that circle around the transistor ? The symbol I used didn’t have it. Does it matter ?

4- What’s the purpose of this switch (and the name of the component)? Is it used to bypass something?

Thanks !

[CTorp]

1- Are those 2x4 headers ? is one male and the other female ?

2x4 or 1x8, it doesn’t matter—as long as they match up. Yes one male one female.

2- I can’t find any component in EasyEDA that looks like a jack input. What do I do ? And I want 2.5mm jacks. Is it ok if I just replace the 1/4 jack for some 2.5mm ? Do I have to modify the circuit ? (This one was 2 questions in one)

It’s in there, I just don’t know what it’s called in easyEDA. For 1/4” vs 3.5mm (I’m assuming you mean 3.5 not 2.5mm) It doesn’t matter which symbol you use in the schematic, but the pcb footprint you’ll select for the schematic symbol will be different.

3- What’s that circle around the transistor ? The symbol I used didn’t have it. Does it matter ?

No it doesn’t matter.

4- What’s the purpose of this switch (and the name of the component)? Is it used to bypass something?

The switch changes the frequency of the delayed signals, High/Low. Check out Sam’s finished module. And it’s a dpdt on/on switch

[Alex1]

Yes 3.5mm ** And there’s no modification to circuit ? Thank you for the answers !

[CTorp]

No modifications, just need to get the right footprint for whichever specific 3.5mm you plan on using.

Also I google searched “easyeda jack symbol” and this pops up, so try and find this one:

.

This is a standard TRS jack, non switched. You’ll notice some jacks have extra pins for switches (normalled pins)

Also, some jacks don’t have the ring connection, (AKA NOT stereo) so are simply called “TS.”

Depends what you are up to! I personally use the same jack symbol and footprint every time and just leave the unused pins unconnected, like what you see in sams schem

[Alex1]

Weird I must have made a mistake. Now when I search jack there’s plenty of them. How can you not spell jakc correctly haha. But I’ll look for this one ! And thanks again for the little course on jack plugs

[CTorp]

@Alex1

How can you not spell jakc correctly haha.

awesome

20 characters

[Alex1]

hahaha
20 characters

[Alex1]

Another question ! a bit dumb

Does it make a difference ? I’d say no, but I’m always wrong. so I’d like someone to tell me I’m right for once.

Please don’t laugh at me…

Thanks !

[Dud]

You’re right, no difference at all

[Alex1]

First win for me thanks. There should be a badge for this !

[Alex1]

Hello !

So I was looking at the components of the schematics I’m re-drawing and I found out that all the resistors are “chip” resistors. And that I don’t want. I used the standard resistor symbol, so I thought they would be standard. But they’re not. Can I still plug normal resistors in it ?

Also, I have reached the stage of placing the potentiometers on the scheme. But I fear that the symbol EasyEDA suggests won’t match the ones I want to buy. Do I need to create a new component that fits exactly what I want ?

[CTorp]

So that is an SMD footprint. There are symbols (schematic) and footprints (physical fit of pcb).

Your symbol is fine, just need to change the footprint.

[Alex1]

oh ok I’ll check how to change the footprint ! Thanks:) So same thing for potentiometers I guess

I found this and I applied to all my resistors