What parts to get at the store? - Page 1
Forum section: electronics / beginners

author: Stonent
author_rank: Super Contributor
timestamp: August 16, 2013, 05:12:06 am
content: Ok I need to start stocking up on some stuff so I need to know what to get. I keep going to the parts store without an idea and buy random stuff but I'd like to go in with a plan to stock up. I always draw a blank when I go there. So I want to go with a list in hand.My idea is to get around 10 of various items. So here's what I've got:Plenty of clear LEDs in various colors2N2222s and the PNP counterpart555 and 556 timersSeveral AVRsMSP430 kitStellaris ARM kit on the waySome NPN darlingtonsXR2206 Func GenSome resistors, ceramic caps that came with my Seeedstudio kitA few small breadboards (2 inch by 3)74HC595Jumper wiresprotoboardPlan to get soon:some 2 line character LCDs (16 or 24 char)So what I'm needing... I need some must haves, something that you'd usually keep at least 10 or 20 of.What common values to keep around? I suspect most of my stuff will be in the 5V range, but would like 12V tolerant on some items.All my projects will be on the hobby level, all through hole / breadboard. I don't have any formal training. (Well I did read a Forrest Mims book as a kid!)Resistors?Ceramics?Electrolytics?Other caps?More transistors?Diodes... I don't have any at all, so I need some part numbers of the types I'd need, Silocon, Germanium, Zener, Schottky others?I'm not really thinking about any logic chips right now unless it's something extremely useful.Other regulators? (probably 317 I'm thinking)What other kinds of chips?Lets say if you had a $20 budget what would you get? What about 40?

author: Skimask
author_rank: Super Contributor
timestamp: August 16, 2013, 06:01:05 am
content: If it was me...and I'm just going on what I've collected over the years in bulk...Resistors?10, 47, 100, 470, 1K, 2.2K, 4.7K, 10K, 47K, 100K, 470K, 1MegCeramics?10pf, 220pf, .1uf (lots), 1ufElectrolytics?mainly in multiples of 10, 1uf, 10uf, 100uf, etc. and a couple big ones.More transistors?2N3904, 2N3906Diodes...1N4004, 1N4148, 1N5819, 1N5822, MBR745"I'm not really thinking about any logic chips right now unless it's something extremely useful."Get a handful of 74xx00 quad NAND's. In a pinch, you can make anything with NAND gates.Other regulators? (probably 317 I'm thinking)LM317 is good enough, if you're aware of it's shortcomings.Other linear regulators, I like the LT1129 series 'cause they've got on/off pins. Past that, 7803, 7805, 7809, 7812, and some heatsinks, plus maybe a couple of negative regulators. But, the 78xx series aren't Low-dropout, so if you've got the option, get some LDO types as well.What other kinds of chips?74138 or 74154 digital demux's, 4066 quad analog switch, 74151 input mux's, generic opamps, TL084 types, 32.768khz crystal, 4/8/10/25Mhz crystals or oscillators, 7474 D flip-flop, 74193...But the list goes on and on...guess you gotta cut what you don't think you'll ever use.

author: vk3yedotcom
author_rank: Frequent Contributor
timestamp: August 16, 2013, 09:09:30 am
content: ^^^^^^^^^A good list above.If you want to do radio stuff you'll want a much better range of ceramic capacitors.Eg 10, 22, 47, 100, 220, 470pF, 1n, 10nOther essentials for RF include crystal diodes, ferrite toroids, variable capacitors and crystals/ceramic resonators at useful frequencies.And for analogue audio stuff you'll want more nanofarad value capacitors, eg4.7, 10, 22, 47, 100, 220 nFSome beefier transistors would helpEg BD139 & BD140. 2N3055 or similar for big power supplies etc.Not to mention various op amp and timer ICs.They're ancient, but why not add LM386 & the 555 as well!Plugs and sockets are also really important if going beyond breadboards and I suggest standardising. I use 2.1mm for 12v input and either 3.5 or 6.5mm for various headphone/microphone connections. Ditto for switches. These can add up greatly so try to get them at a good price (though quality can also suffer).

author: Stonent
author_rank: Super Contributor
timestamp: August 16, 2013, 02:00:08 pm
content: I do have some 555s but don't have any LM386s. I probably need more analog stuff.

author: bbarbour
author_rank: Contributor
timestamp: August 16, 2013, 03:18:55 pm
content: Some argue against "stocking up" and prefer to purchase what you need at the time. It's certainly the cheaper route but what I did was raid Ebay. Find the guys with 200k positive reviews in China and purchase in bulk. I bought 2,500 assorted 1% resistors for $8 (USD), free shipping. I bought a bag of 400 electrolytic caps for $11. Granted these components are not quality enough to be used in a real product, but they get the job done for a hobbyist/prototyping. Sometimes you'll also find people selling off the contents of their grandfather's garage which can net a pretty nice grabbag.The lists above are pretty good. What I've done is browsed various video and web tutorials and as a component is mentioned, I look it up and buy a few if it sounds interesting. You'll quickly realize which components are used often and which are highly specific.

author: edavid
author_rank: Super Contributor
timestamp: August 16, 2013, 04:09:18 pm
content: Your store has really high prices... if you want to stock up, you should use mail order, and save the store for immediate needs.

author: AG6QR
author_rank: Frequent Contributor
timestamp: August 16, 2013, 05:23:40 pm
content: One thing I don't see listed yet, and which I never seem to have enough of, is connectors. Exactly which connectors you need depends on your type of work, but BNC, Banana plug/jack, DE-9, ribbon cable/header connectors, 1/8" mono and stereo audio jacks, plus a few common coax power connectors seem to see a lot of use.Switches are another thing that I like to buy in person rather than mail order, because there's no substitute for handling one to feel the quality.

author: Stonent
author_rank: Super Contributor
timestamp: August 17, 2013, 05:21:31 pm
content: Ok I ended up with most of what was suggested and a few useful add-ons:I went over my budget of $20 so some parts got left out or weren't available.Chips:1 x Max232A1 x LM3862 x LM3171 x LM336 2.5V Reference2 x 741C Op-AmpsResistorsI got 5 of each suggested. 1/2W 5% for now. If I can find a good deal on some 1% ones I'll stock up in a larger quantity.They also had by itself a 32 pack of 1K 1% 1/4W for 69 cents which I picked up.There was a small selection of .1% 1/4W parts so I got 1 each of everything they had which was 20K, 40.2K, 12.1K and 126K.Caps:(Sold out of 10pf)5 x 220 PF5 x .1 uF5 x 1 uF electrolytic (they didn't have any ceramics this high)5 x 10 uF5 x 100 uFTransistors, Diodes and Rectifiers.They didn't have a few of the parts recommended so they either got omitted or replaced with a part with similar specs or next lower voltage range10 x 2N390410 x 2N39061 x BD1391 x BD1381 x BD4341 x BD677A1 x BD679A10 x 1N40045 x 1N581715 x 1N41481 x DF04 Bridge RectifierMisc:1 x 10 pin 1 foot ribbon cable with female headers1 x PC-016ATE 2 x 24 LCD (Hitachi based)1 x 50K Thermistor (heat shrunk with 1 foot leads)

author: Crazy Ape
author_rank: Regular Contributor
timestamp: August 17, 2013, 06:42:36 pm
content: Do you have any ideas for a project?

author: Tita
author_rank: Contributor
timestamp: August 17, 2013, 07:50:55 pm
content: Lots of 100nF capacitors!1000uF/10uF/220uF/470uF/4,7uF/1uFThe most common resistors values:100R;1k;10k;100k;220R;470R;1R;IC:NE555;LM386;LM324;transistors: 2n2222; bc548;2n3055 ,bc547 etc;diode: 1N4148;1N4007;1N4001