Cart or BOM for beginners looking to stock up?

Hello everyone,

I’ve seen the cheap component thread and found it to be incredibly helpful. I was wondering if anyone had made a cart for Tayda/Mouser/etc. that had a little bit of everything in it, say if someone wants to have a really good stock of components to start out with, so they can reach for it at will.

I know that almost every circuit is going to require a proprietary component/IC of some sort, I’d just like to have everything else available when said proprietary components arrive in the mail!

If not, I guess I’m up for the task! I was actually going to go in and do it myself, but stopped when I saw all the sheer number of options of different capacitors on the ‘easy component search’ pages. Could I use the values that are found in this kit (or similar) as a guide for putting together my own cart from Tayda?

Same goes for resistors and other components, can I use the values in kits as reference for which ones to buy for myself? Thanks, looking forward to getting started!

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That one is probably overpriced, but I got some multi packs of Rs and Cs from AliExpress that have served me well.

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The only reason I haven’t just bought a ton of those kits is because I feel like I’ll run out of 25 of the same cap almost immediately! Optimistically though, I’ll take that to mean that I can limit the caps in my Tayda cart to just the ones that come in the pack. if all goes well, I’ll be back shortly with a ‘Cart for Beginners!’

Welcome @hitachii , it’s a good question. I keep a notebook (a Personal Analogue Device or PAD for short) where I keep a note of things running low. I then spend time looking for found, free, recovered or alternative before I buy.
I don’t recommend stocking up usually but planning ahead. I have a stockpile of projects in bits, in plastic boxes with a note ( a useful detachable ‘file’ available with a P.A.D.), listing the BOM and ticking off what’s in the box. I build when the list is all ticked. Resistors are my only exception and buy ‘kits’ of various sizes now and again.

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That sounds like a good plan! Things that I buy in packs of 100 at least:

resistors

  • 100k
  • 1k
  • 10k
  • 20k
  • 47k
  • 470k
  • 1M
  • 2k
  • 4.7k
  • 100
  • 220

(for resistors it’s almost always a good idea to buy at least 100, they are much cheaper per piece at that point in most places. By now I only buy less of a value if it’s a very rare value, like 49.9 ohms, or something like that)

capacitors

  • ceramic 100nF
  • ceramic 10nF
  • (ceramic 1nF?)
  • EL 10uF
  • EL 1uF
  • EL 100uF
  • EL 4.7uF

Enough big 4700uF for you power supplie(s), usually there are 6 needed for one power supply board. Make sure those have enough voltage rating (at least 25V, if I remember correctly)!

diodes

  • 1n4148
  • 1n4004
  • LEDs in the colors you like

transistors

  • 2n3904
  • 2n3906
  • maybe BC547?
  • maybe BC557?

connectors

  • 10 pin IDC sockets (whats the correct name?), you want shrouded, so you can not reverse the cable!

  • 16 pin IDC sockets (whats the correct name?)

  • pin headers 2.54mm in various lengths

  • pin sockets 2.54mm in various lengths (with most you can buy large ones and cut them to length)

  • ribbon cable (I would get 5m or 10m for a start)

  • jack sockets! many many jack sockets!!

  • maybe molex connectors, if you want to use this style of connecting and not mount the jack sockets on the PCB

potentiometers and switches

These are expensive, so depending on your budget you might want to keep those to a “minimum”. But in the end you always want to build more modules and you always need more, so maybe just buy a lot! :laughing: (but not so many that the places run out of them and no one else can build anymore, looking at you, Megadrone :grin: )

  • 100k

  • 10k

  • enough caps!

  • SPDT switches (on/on),maybe (on/off/on)

  • DPDT switches (on/on), maybe (on/off/on)

  • trimmers, 100k, 10k, 1k (not a 100, but 20, to 30 each is good to have, I would say)

opamps

  • tl072
  • tl074
  • maybe lm13700?? you do not need 100, but they are common, so maybe 10 for a start?
  • sockets!! not only for opamps, but for all you ICs, so buy several sizes!

regulators

  • LM7805
  • LM7812
  • LM7912

I probably forgot half of the stuff, but others could add! Can I make my post editable by everyone?

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This is amazing @sebastian thank you!!!

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3 dots → Make Wiki

Can we move Sebastian’s post into the FAQ category @Caustic ?

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I too generally just plan ahead, see what I need for the modules I want to build, but always get extras — you never know when a part’s going to get fried or lost or something — with the result of ending up with a stockpile mostly of commonly used parts. After some time you get a feel for what parts you use a lot of and can stock up on them. It’s hard to get agreement on them, though, people tend to build different sorts of modules that require different distributions of parts.

I try to keep a few of most E24 resistor values, at least in the 100R–1M range. Some values I buy 50 or 100 or 200 of at a time, not that many though — yeah, they’re cheap, but some values you just won’t use 100 of. Likewise I buy lots of a few capacitor values and types (don’t neglect film!) I use a lot of but mostly I get them and a few extra on an as needed basis. Jacks definitely, and B100k and B10k pots — but not too many because there’s panel mounted, board mounted vertical and horizontal 9 mm and 16 mm, all in 6 mm or 6.35 mm shafts; expensive to buy a lot of each of those and then not use them. And I buy knobs in bulk. TL072 and TL074 chips (I have some TL071s but they’re not used that often), and LM13700 which you might have trouble sourcing in the future. 8- and 14-pin sockets. 1N4148 and 1N5817 diodes. 2N3904 transistors, and fewer 2N3906. Or BC547 and BC557. Generally you can substitute the former for the latter (turned around 180° though) and most other BJTs you see in circuits can be replaced with one of those. SPDT switches. 40-position pin sockets and headers to cut to length, 10-pin shrouded headers, 10-pin IDC connectors and 10-conductor ribbon cable. LEDs, I mostly use 5 mm green ones but if you’re using someone else’s panel you might need 3 mm and the color is a matter of taste. (No, I can’t taste color.) 2- and 3- position Molex headers and connectors. 24 AWG stranded hookup wire in a few colors, and some solid hookup wire — more of that if you do a lot of stripboards. I think that’s most of what I can reasonably count on finding in my supplies, anything else might be there or might need buying as needed.

Also see:

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Presenting the Synth Starter Cart!

the goal was to put together a cart for >$150 (my meager budget) while getting enough stuff for at least a few modules.

I based the supplies off @sebastian and @analogoutput helpful lists and links, as well as the other helpful parts thread here.

It’s missing the large caps used for power supplies. I can go back and add those tho I’m unsure that they’re universal (I’m using 25v 3300uf for the PCB I bought).

Please feel free to edit and update this list if there’s anything on there that I’m missing! Thanks for the help everyone!

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Why the TL084? They’re produced on the same die as the TL074 but are tested after production and labelled according to noise.

I would leave out the shift registers, hex inverters, and NAND gates as they’re only really for specific use cases.

For Kosmo folks the 3.5mm jacks should be replaced with 6.35mm.

How about adding some 1N5817, they are commonly used in module reverse polarity protection (or 10R resistors, ferrite beads, flavour to taste.)
Are you building 15 power supplies? That’s an awful lot of ±12V regulators.

Hopefully some constructive feedback there :wink:

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I invite the feedback! Forgot to ask for it in the post.

The TL084 is actually for a personal project (Shruthi Polivoks VCA). iirc the voltage regulators are called for in the filter as well so I figured they were more common than they probably really are.

That’s great, I’m more than happy to save the money on those. How about the caps? There are so many variations I never know what kind to get!

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I have just taken a quick look at your cart, Just a couple of comments

  • you have more ic’s than holders
  • In general 2 No 0.1uFceramic capacitor per IC plus a few spares, I would just buy 100, you will use them.
  • 2 No 10uF capacitors per project plus a couple of spares
  • Most euro rack led’s are 3mm, Kosmo 5mm
  • 10-ohm resistors, these are used on the power rails of a lot of modules, and often in place if ferrite beads.
  • I find I use a lot more 100k resistors than any value, some modules can use 30 or more.
  • The 1uF, I would buy some film and some ceramic, not electrolytic.
  • I’ve not used many 100uF caps,60 sounds like a lot to start with, you could buy 5.
  • The transistors, I would buy 1 2N3906 for every 10 2N3904
  • Some modules have 7805 regulators, 7812 and 7912 are usually just on the PSU, given the size of your order 5 No 7805 will get you off to a good start.

I hope some of these comments help.

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I hardly every use polarised electrolytics. I do include a footprint for 2 10uF caps on most of my modules as they’re called for in the L7805 datasheet, but the majority of the time I don’t bother soldering them on.

L7805 regulators are common in digital modules; 15 of those is ok, but the L7x12s are only used in power supplies and aren’t nearly as common.

Depending on what your power supply is, you might need more or less of the 10/16 pin box headers and IDC connectors. For example, I only use 10 pin cables and connectors because thats what my power supply and modules use. Some Eurorack bus boards use 16 pin headers but most modules use 10 pin, creating the need for 10 pin to 16 pin adapter cables. In 95% of cases, a 16 conductor cable is unnecessary because the module has 10 pins.

Regarding the LM13700s, I think it’s wise to plan ahead and see which modules you plan to build and how many you actually need. They make up 10% of the total cost!

FYI, 3mm LEDs are tiny; 5mm are the most common.

I notice you haven’t included 9mm PCB mount pots; they are more slimline and common on PCB projects.

One final thing - you can never have too many 100k resistors! I tend to order them alongside op amps - 1 per op amp unit.

Edit: the truth about ferrite beads:

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Oops! @Dave beat me to it.

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On the other hand, they may be 20% of the cost in six months, if you can even find them then! As I noted in another topic, bizarrely, Mouser has them for substantially less than Tayda is charging. For those just tuning in, the DIP version of LM13700 is out of production — and it’s used pretty widely in synth DIY, being one of the few OTAs (recently) available. Hopefully Alfa or someone will bring a clone to market but right now… let’s just say I’m glad I stocked up when they were $2 each.

In fact the pots included are ones I hardly ever use. For one thing they’re knurled shaft and I prefer round, but aside from that they’re horizontal board mount, which I don’t see called for in a lot of designs… some, yes, but not a lot. And I haven’t used them so far in any of my designs. That’s the trouble with pots, as I said before, there’s so many options — body diameter, shaft diameter, shaft type, audio taper, linear taper, panel mount, board mount horizontal, board mount vertical — and different module designers tend to favor different styles. So stocking up on pots can be problematic. There especially it’s best to get just enough of what’s called for in the particular modules you want to build, plus a few extra.

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Should I buy a bunch of film caps as well? I’ve never used them but I see that Moritz Klein seems to use them almost exclusively.

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Some people swear by them; for my hobby stuff I use the cheapo ceramic ones and they work fine.

(that said I think my 3340 VCOs might benefit from a decent timing cap.)

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Other than a few 1uF film caps, I order them on an as-needed basis.

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I favor film for anything 1 nF – 1 µF that’s in the signal path, but you certainly can get away with good ceramics. Definitely cheap ceramics for bypass caps! But I agree with @Dave, get them (and some extras) as needed. It’s too hard to predict what you’ll be using.

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