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I came across Ben Eater's Youtube channel and website and thought I'd give the clock circuit a shot (possibly doing the entire 8-bit computer thing in the future). He conveniently put list of items online what's in the kit. I wanted to order it from him, but shipping is quite expensive as I am not based in the US.

I can find basically all items, I do have some trouble finding the ICs though. One is a Hex Inverter 74LS04, but I cannot find that one (and also not the 74LS08 and 74LS32).

When searching for an inverter I do find the 7416, could that be a decent replacement (I checked the datasheets, and I don't really see a big differences). Same for the AND and OR gates, can I safely use ones that look the same on the first look?

Bart Friederichs
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    The 7416 is not a direct replacement for a 74LS04. It has open collector outputs (hence the "high voltage") and needs, at the very least, some pull-up resistors on its outputs.But even then, it will not behave exactly the same as a 74LS04. You might look at the 74HCTXX family which seems to be somewhat easier to find. It's not advisable to use ones that simply "look" the same as many parameters have to match for reliable interaction with other logic ICs. – StarCat May 03 '20 at 17:36
  • Note that the way Eater uses the chips is not going to be compatible with all 74-series chips also. If I remember the videos correctly, he drives some LEDs directly from the outputs, which is fine for a 74LS chip but will destroy the LED if you use it with a 74HCT. – Hearth May 03 '20 at 17:56
  • What can you get? If used in the "approved" manner you could replace 74LSxx parts with 74HCTxx, but where they're used "off label" as @Hearth points out, you can't. Basically, if the parts are hooked up so their outputs go only to other chip's inputs, and there's no resistors, capacitors (aside from decoupling), LEDs, etc., involved, then you can just replace them straight across. Where Ben is playing analog tricks, you can ask here. – TimWescott May 03 '20 at 18:38
  • Pretty much any logic family should work... namely 74F, 74HCT, 74HC (CMOS thresholds at cca 0.3 and 0.7 * Vcc, otherwise 5V-powered too), 74AC/ACT and the like. Note that 74F, 74AC/ACT and 74ABT are pretty fast = be sure to place a power blocking capacitor (ceramic) as close as possible to the DIL chip's power leads. Note that most of these chips are nowadays available in at least two different packages: e.g. a through-hole (THT) version in 2.54 mm raster, and a surface-mount (SMT) package in 1.27 mm or finer raster. You won't plug the SMT version into a solderless breadboard. – frr May 03 '20 at 18:44
  • And yes, pay attention to the basics. Such as putting resistors in series with LEDs. Try to understand what you're doing, rather than build things based on a recipe, without a clue how the circuit approximately works. Come back to ask principal questions. – frr May 03 '20 at 18:47
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    Thumbs up for playing around. You'll probably find out that building a "computer" out of DIL packages is mostly moot, but if you like tinkering, you may find the journey worth more than the textbook example results. This stuff is an endless play thing - bordering on computer programming, basic robotic stuff, industrial process control etc. I assume that you are a student... the knowledge of principles that you gain this way can come in handy in a number of carreers or fields of study. During my own beginnings in the pre-Internet era, skilled mentors would've been useful. Feel free to ask :-) – frr May 03 '20 at 18:56

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Generally, without having looked at any of these chips in particular, yes:

What you need here is the same functionality – if it's from the same logic family (LS), then it will react to compatible voltage levels.

You'll need to make sure these are actually the same functionalities – e.g. some things have push-pull outputs, other open drain, some things have tristate logic, others not...

Timing would not necessarily be the same – but considering this is breadboard, it's very unlikely that timing restrictions arise from the logic gates; the thing will be limited by the wiring parasitic effects.

Marcus Müller
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  • Thanks a lot for your answer. I did find the 'original' items somewhere, but your advice will surely come in handy along the way. – Bart Friederichs May 03 '20 at 17:48
  • Hej Bart, thanks; I was a bit confused, because Mouser does most certainly ship these things to the Netherlands. – Marcus Müller May 03 '20 at 17:50
  • Oh, Mouser only ships them expensively :( – Marcus Müller May 03 '20 at 17:53
  • @BartFriederichs but Farnell is pretty OK – Marcus Müller May 03 '20 at 17:55
  • Speaking of carriage to NL, check out TME (Poland) and maybe Conrad (not sure if Germany or Austria). – frr May 03 '20 at 18:38
  • @frr Conrad is from Germany; yeah, but I think Farnell even ships for free to the Netherlands (at least I think they did at some point), hard to beat that :D Reichelt is another European option. – Marcus Müller May 03 '20 at 19:19
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    @Marcus Müller oh you're right, Farnell have a warehouse in Belgium. That would explain free Shipping to NL. Similarly, TME in Poland have fairly cheap shipping to us in CZ. Apart from the geographical closeness, I guess they even dispatch their parcels for CZ daily (twice daily?) in a common container or some such and hand that over "en bloc" to a parcel carrier in CZ for "domestic" dispatch. And that first hop from Warsaw to Ostrava even flies by an airplane I guess... (based on the fact that batteries and chemicals take a day longer to deliver, due to road transport instead of air freight) – frr May 03 '20 at 19:59
  • @MarcusMüller free shipping from €50, and I needed other things as well (threw in an Arduino just for fun) – Bart Friederichs May 04 '20 at 06:19