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I'm trying to make my own version of this, but I can't for the life of me find where I can get those little springs for the solderless connections. Does anyone know who makes them/where I can get them?
imho you should use Fahnestock clips instead. More durable, professional, and easier to insert. Those spring things are actually pretty custom.
Oooo. Thanks for the advice! I had no idea that's what those were called. I will use those for sure as they are much easier to find.
So turns out those are just about as hard to find.
I did find this small diameter spring stock on McMaster. I think it'll work well for what I need. Now I need to work on the layout.
You can literally find them anywhere, but whatever. Good luck!
I played so much with the Radio Shack kits that I feel I should point out their springs were standard on the top but tapered by about 20% in the bottom half that went into the cardboard backing. That made them sit more firmly in the backing, to my memory, because they basically screwed in.
Yeah, I remember that too. I actually still have mine in the garage somewhere, but it turns out that those springs are custom and perhaps due to my inability to find things as pointed out by Mateo, I can't find that kind of spring anywhere.
This is my current layout for the board. Please respond with suggestions for improvement!
A few thoughts:
  • Any particular reason why 8 NPN transistors but only two PNP transistors? Planning to focus more on TTL logic circuits than analog circuits, for example?
  • I hope those resistor values are just placeholders, again, if you're planning to have more than just digital circuits (same with the capacitors)!
  • The way these kits work, where you can chain springs together, the row of grounds and VCCs at the bottom feels unnecessary to me.
  • If you're planning to do anything with analog audio, having an audio transformer on the board is probably good.
I am planning to do more TTL logic than analog, I should have clarified. If I need to do analog circuits I still have the old kit that is very well suited for that.

What would you suggest for resistor and capacitor values? They were more or less placeholders.

I know that when you jump ground or something to somewhere you can just pull ground from there instead, so I guess that does kinda invalidate the two planes at the bottom. I thought it might make the wiring look neater? I do see why it could be seen as unnecessary.

EDIT: I should also clarify that the two IC's on the left are sockets for plugging in any IC that you want up to a 16 DIP package.
Why so many diodes? I'd use like 6 maybe, 4 geranium and 2 selenium. I guess I could see a zener, but 9 diodes seems excessive.
Yeah, the amount of diodes is kinda high. I agree with that. I could cut that down but to make room for what?
Botboy3000 wrote:
Yeah, the amount of diodes is kinda high. I agree with that. I could cut that down but to make room for what?

I see no leds or 8 segment display Razz
OMG! How could I forget LEDs? If I'm doing TTL logic of course I'd need to have some of those. To add LEDs though I might also need to cut down on resistors... Maybe Kerm's suggestion for resistor values will lend some insight on how to cut down.
Just to follow up with what was discussed on SAX
Quote:

[12:03:36] <geekboy> Id also make sure you have at least 1 resistor per led and BJT
[12:03:45] <geekboy> and maybe throw a mosfet or 2 on there?
[12:04:04] <saxjax> [Botboy3000] hmm yeah, not a bad idea
[12:04:35] <saxjax> [Botboy3000] I would wire resistors in for LED's under the hood
[12:04:57] <geekboy> IMO thats not a great idea
[12:05:08] <saxjax> [Botboy3000] really?
[12:06:29] <saxjax> [Botboy3000] what's your reasoning?
[12:07:05] <geekboy> Well let me rephrase
[12:07:17] <geekboy> its not a good idea if its not on the top of the panel in writing or pysically
[12:07:46] <geekboy> SO you dont assume its not there


I would also recommend a NE5532 over that LM741 that gets you 2 op amp channels instead of a small calibration pin, Rational is for small circuits and testing on something like this a little bit of error should not make a huge difference. To the point of having a second op amp available definitely out ways that in functionality.
I agree with the replacement of the LM741 with the NE5532 completely. Thanks for the suggestion! I will also be putting 2 mosfets in place of the power and ground rails at the bottom, and replacing some of the rows of capacitors with LEDs.
Updated layout. Now there are 8 LEDs and 2 mosfets in place of some of the capacitors and power rails.
Also I replaced the LM741 with the NE5532.

Something I considered was replacing some of the diodes with tactile switches. Thoughts?
  
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