Author Topic: From no parts to decent stockpile, best approach?  (Read 339553 times)

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Offline wizard69

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Re: From no parts to decent stockpile, best approach?
« Reply #225 on: April 05, 2020, 08:26:56 pm »
As for being worth you money, i think the simple answer here is could you buy all of this for less?   Most likely yes because it costs money to create the kits.
Not sure about that. It seems that some parts cost much more on DK or Mouser than in kits or on Ali, probably because of very high margin.

it isn't exactly "fair" to compare a kit from China with DigiKey's mainline products.   My point is you are still paying for kit box and the time it takes the vendor to assemble the kit.   that might not be a bad thing depending upon what you get exactly in the kit.    If you went to Ali express and purchased in bulk, which might make sense for resistors, you likely would have far more material for each dollar spent.   On the flip side you might end up with far more than you will ever use.

In any event I actually liked this kit because it does details exactly what you are getting and appears to avoid a lot of useless high value resistors.    I'm just not sue it makes sense for everybody, I'm still a fan of buying when you need something.
 

Online Gyro

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Re: From no parts to decent stockpile, best approach?
« Reply #226 on: April 05, 2020, 08:34:25 pm »
As for being worth you money, i think the simple answer here is could you buy all of this for less?   Most likely yes because it costs money to create the kits.
Not sure about that. It seems that some parts cost much more on DK or Mouser than in kits or on Ali, probably because of very high margin.

Probably because of genuine spec, in-tolerance components versus low quality or production line reject parts more like. You can't compare Ali parts with main line distributor ones.
« Last Edit: April 05, 2020, 08:41:35 pm by Gyro »
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Offline Codealot

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Re: From no parts to decent stockpile, best approach?
« Reply #227 on: April 06, 2020, 02:02:46 am »
Probably because of genuine spec, in-tolerance components versus low quality or production line reject parts more like. You can't compare Ali parts with main line distributor ones.
This may be the case for semiconductors and possibly even resistors, but no way it justifies their prices on cables and connectors.
 

Offline DrG

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Re: From no parts to decent stockpile, best approach?
« Reply #228 on: April 12, 2020, 05:47:35 pm »
I think my approach has been a hybrid of already mentioned strategies. One that I find particularly relaxing sometimes is salvaging....

This cheapo DVD player that worked for a short time (a long time ago) before skipping around a lot...

[attachimg=2]

becomes...

[attachimg=1]

Not a huge haul, but some usable material...

25Q80 spi memory chip - I read the stored BIOS using a cheap programmer. Have not yet written it and tested it thoroughly.
ORPC-817 optocoupler (tested good).
3 x DC motors (all tested good).
s9014 GP npn (not shown but has good legs)
some switches - 1/2 dozen momentaries (all good) and a nice swivel switch (for lack of a better term).
usable padded feet and cables/sockets
a few other miscellaneous.

Much better this way than to leave it in the junk box until it is tossed.
I have not yet decided on the WTP-AD01 (the optical pickup). I might have a use for it some day, but will probably keep it as until I do some more reading.
« Last Edit: April 12, 2020, 06:03:14 pm by DrG »
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Offline eugenenine

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Re: From no parts to decent stockpile, best approach?
« Reply #229 on: April 12, 2020, 09:02:52 pm »
Leave the motors attached to the dvd mechanism unless you have a use for them at the moment.  There are projects around those complete mechanisms and its easier to leave them together then try to match up the right one later :)
 

Offline DrG

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Re: From no parts to decent stockpile, best approach?
« Reply #230 on: April 12, 2020, 09:14:35 pm »
Leave the motors attached to the dvd mechanism unless you have a use for them at the moment.  There are projects around those complete mechanisms and its easier to leave them together then try to match up the right one later :)

Yeah, I thought about that, and you have a point, but I decided against it.
I looked for quite a bit for projects and didn't find anything that I could really get into seriously. Lots of clocks and lots of balloon busters / burners but those are for DVD R/W drives using the laser (and some pretty sketchy projects with regard to safety).

I did think about using the WTP-AD01 with a controller as a moving target (that motor can be reinstalled easily)....but I need a semi useless project like I need a ________.  :)

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Offline boffin

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Re: From no parts to decent stockpile, best approach?
« Reply #231 on: April 13, 2020, 04:11:44 pm »
I think my approach has been a hybrid of already mentioned strategies. One that I find particularly relaxing sometimes is salvaging....

This cheapo DVD player that worked for a short time (a long time ago) before skipping around a lot...

[attachimg=2]

becomes...

[attachimg=1]

Not a huge haul, but some usable material...

25Q80 spi memory chip - I read the stored BIOS using a cheap programmer. Have not yet written it and tested it thoroughly.
ORPC-817 optocoupler (tested good).
3 x DC motors (all tested good).
s9014 GP npn (not shown but has good legs)
some switches - 1/2 dozen momentaries (all good) and a nice swivel switch (for lack of a better term).
usable padded feet and cables/sockets
a few other miscellaneous.

Much better this way than to leave it in the junk box until it is tossed.
I have not yet decided on the WTP-AD01 (the optical pickup). I might have a use for it some day, but will probably keep it as until I do some more reading.




Is it really worth scrounging things like an 8050 transistor or 817 opto when those items are readily avail from a legit distributor (LCSC) for a few cents each (S8050 = 1.6c/ea, 817 2.9c/ea and that's in 10 lot).

Keeping an old board and if you don't have the component doing a quick scrounge makes sense, but pulling apart everything in advance?? (I admit I did this when I was a young teenager, but at that point parts were 10x the price). Back in 1979 a BC107 tranistor was 15p (UK), now I can buy them for 1/10th of that price and that's not adjusting for inflation.


 

Offline DrG

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Re: From no parts to decent stockpile, best approach?
« Reply #232 on: April 13, 2020, 05:02:48 pm »
I think my approach has been a hybrid of already mentioned strategies. One that I find particularly relaxing sometimes is salvaging....
/-- snip --/




Is it really worth scrounging things like an 8050 transistor or 817 opto when those items are readily avail from a legit distributor (LCSC) for a few cents each (S8050 = 1.6c/ea, 817 2.9c/ea and that's in 10 lot).

Keeping an old board and if you don't have the component doing a quick scrounge makes sense, but pulling apart everything in advance?? (I admit I did this when I was a young teenager, but at that point parts were 10x the price). Back in 1979 a BC107 tranistor was 15p (UK), now I can buy them for 1/10th of that price and that's not adjusting for inflation.

I still favor this approach as a complement for parts accrual, BUT, with certain qualifications.

IOW you raise some good points. In fact, I looked up the motors and, sure enough, you can get them new for ~$1-2 US$. The memory bios chip was a surprising plus, but still probably only a buck or two. I already have a few of those IR sensors (1838 type) and so on. I have at least 25 opto's, none are 4-pin though (all older 6/8 pin - many salvaged and some high-gain darlington types that I bought). Optos are easy to test for suitability in my own projects. The switches probably will get used at some point. The cables and connectors *might* be useful - it is infuriating to need one and have little choice but to have to order it and wait.

There was plenty of stuff that I left alone (most of the power supply components).

Here are the general rules that I practice.

I will not give in to the compulsion to scavenge everything possible (I have to admit that if it was a small board, I might have at one time, removed, everything removable).

I no longer bother with scavenging the item, if it is fried or I have good reason to believe it is fried unless there are some specific things that I need AND can test out. An example is an old discarded radio that I scavenged for only the ferrite coil antenna and the telescoping antenna (both are in use right now).  When I opened it up, it was clear that at least one capacitor had leaked. I don't want inexpensive components that may be flaky, even to play with.

I don't (no longer bother with) scavenging the item for simple resistors and capacitors with very short leads. If that is all you can get, I understand and will not criticize.

I do scavenge nuts and bolts. I frequently search for small hardware like those and I can sort them in a bin as they are being removed (in contrast to dumping a large jar and trying to find the right ones).

Finally, I have to be in the right mood to scavenge and when I am, it is a relaxing activity. I have a hot air station and it is a little game (some kind of skill there) to remove items easily. I reduce the junk pile and add to the component pile.

That's my story and I am sticking to it  >:D
- Invest in science - it pays big dividends. -
 

Offline El Rubio

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Re: From no parts to decent stockpile, best approach?
« Reply #233 on: April 27, 2020, 12:54:15 pm »
Probably because of genuine spec, in-tolerance components versus low quality or production line reject parts more like. You can't compare Ali parts with main line distributor ones.
This may be the case for semiconductors and possibly even resistors, but no way it justifies their prices on cables and connectors.

I have to agree with Gyro, especially with cables and connectors. For example, Mini grabber clips for test leads. Got 10 pairs for a few bucks from China. Absolute garbage. I made 5 jumpers and destroyed one in normal use before I used it 10 times. I went to a local electronics supplier and got some Pomona mini grabbers. The were a few bucks each, but the quality is so much better. I wouldn’t be too concerned about resistors or ceramic caps from chinese discounters like Ali, but I wouldn’t buy semiconductors, or most any connectors- banana, rca, and especially RF connectors unless it is the last option.
Personally, it takes so long for something shipped from China to make it here that I usually forget why I ordered it to begin with. Plus, I’m kind of pissed at them for their actions during this pandemic.
 

Offline dbctronic

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Re: From no parts to decent stockpile, best approach?
« Reply #234 on: April 30, 2020, 06:12:48 pm »
I agree with El Rubio and Gyro about not buying certain parts. Connectors really can be just a complete waste of money at any price. RCA phono connectors that melt when you try ever so carefully to tack solder leads to them, shells that don't hold the connector body tightly...  no thanks.
And as for Chinese semiconductors, I don't buy 'em because I don't buy any semiconductors if I can't get decent datasheets for them. American made stuff almost invariably has good ol' JEDEC standard sheets. Chinese... anything from not available, to mostly Mandarin with a gloss of English, to strangely worded and organized, and obviously incomplete. I wouldn't have them for free. I'm not an engineer trying to hold down costs on things made by the 10,000s, just an amateur who can't stand to waste time making one-offs with junk that needs debugging and patching. And that's assuming you have the datasheets you need to do the debugging. Their '2N3904' may not be quite standard, and their datasheet may or may not tell you the differences...
And yes, they have misbehaved about their little unintended export, and its world changing consequences.
 

Offline DSE_Kid

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Re: From no parts to decent stockpile, best approach?
« Reply #235 on: May 06, 2020, 10:27:50 am »
Some great tips here! When I started as a hobbyist all my parts came from discarded electronics on the side of the road. These I work on vintage tube electronics and for the most part the only parts I'll buy new are electrolytics, everything else has a pretty decent shelf life.
 

Offline Electro Fan

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Re: From no parts to decent stockpile, best approach?
« Reply #236 on: May 06, 2020, 06:26:26 pm »
I’ve watched this thread develop.  Some good ideas and some humor in here.

I’m not sure if my idea belongs here or in the TEA thread but I’ve come to the conclusion that for most electronics enthusiasts it’s only a matter of time until your parts strategy will be constrained by either your budget or space and by that time you will either have implemented a storage and inventory management system that works for you, or you will spend some time trying to figure out how to better organize your your parts, bench, and lab. Along the way your significant other and friends might wonder how you work and live in there, and they will be impressed if/when you figure it out.   :)
 

Offline IJL05

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Offline dbctronic

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Re: From no parts to decent stockpile, best approach?
« Reply #238 on: May 15, 2020, 05:00:03 pm »
DSE_Kid is right. Old electrolytics are garbage. And just quickly testing them doesn't help much - an old tube radio that's been sitting around for decades has a distressing tendency to work for a few hours, then go south. The electrolytics grow an insulating layer that soon fails in use. If you buy old tube equipment, best idea is to just blanket replace 'em all first thing.
 

Online tunk

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Re: From no parts to decent stockpile, best approach?
« Reply #239 on: May 15, 2020, 05:08:11 pm »
GreatScott recently posted this video:
 

Offline JLCPCB Official

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Re: From no parts to decent stockpile, best approach?
« Reply #240 on: June 09, 2020, 05:07:37 am »
Hello ;

Cool kit as long as you keep them well arranged, specially the small components need to be all the time sorted, usually perform a sorting task for small stocks like once per month will help you keeping all you workspace organized and this way it will not be a "wasting money"  ;)
 

Offline VictoriaMcLean

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Re: From no parts to decent stockpile, best approach?
« Reply #241 on: June 19, 2020, 07:35:56 pm »
Thanks for sharing.
 

Offline Cliff Matthews

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Online RJHayward

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Re: From no parts to decent stockpile, best approach?
« Reply #243 on: July 30, 2020, 06:51:22 pm »
Try look at drugstore shelves for 'Pill Organizer' boxes:
  Picture shows weekly boxes, I use there for all sorts of tiny screws / any tiny parts (that don't have static protection issues). Some 60 compartments shown right there, plus you could make a holder frame about
8 by 8 inches.
  Try exp with NAIL POLISH for marking each.
  People doing bead work use vials for storage, I think.
- RJ[attachimg=1]
 

Offline Frankenstein

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Re: From no parts to decent stockpile, best approach?
« Reply #244 on: September 12, 2020, 08:25:33 am »
Hi, yes I want a a small bag of PCB common components
And have to buy a million of each ... when you find out let me know I’ll keep looking and reciprocate
Many thanks !!
 

Offline pvsage

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Re: From no parts to decent stockpile, best approach?
« Reply #245 on: November 21, 2020, 05:52:25 pm »
Late to this party, but I just had to chime in: a small selection of inductors is good to have on hand, especially if you plan to roll your own regulated supplies or throw in an LC filter for something powered by a dirty wall wart. I have a set I got from "the usual scumbags" at eBay for under $10 and it came in handy a couple weeks ago. (Perspex droplet barrier due to COVID, couldn't hear customers clearly - electret mic, LM386, cheap tinny loudspeaker in a shopping box, dirty 12V supply. LC filter cleaned up the power supply noise.)
 

Offline m k

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Re: From no parts to decent stockpile, best approach?
« Reply #246 on: November 21, 2020, 07:51:52 pm »
Around here buying has two routes, with or without shipping.
Local is with 15-20€ and China is without or minimal.
(one is compensating the other)

Last local order was few PIC chips when need is one but they are quite general purpose.
Last China order was few thousand discretes.
(China route is long)

I've been around since the eighties and seen integration and Moore's law in action.
Based on that I'd say that stocking something special is more a miss than a hit.
Ie. I'm quite sure I still have few tubes of DIL DRAMs and UV EPROMs.

I've also thrown away literally truck loads of stuff.
(maybe two)
Not missing much, maybe some power parts, like few bags of heatsinks.
It's always irritating when you need to buy them back.

Edit
v

Those cartboard boxes are very good, you can also get them as deep as is needed and so use the whole shelf.
Actually so good that you become so lazy that adding an occasional box in between makes you whine about the work load.
(and we only had a few dozen shelves)

Since vertical direction is usually free, something there would be nice.
How about a stackable oval carousel with curtain holder rails and hooks with bags.
Maybe then one could learn to keep part of the table empty.

Normal revolver cabinet in small scale would also be nice.
Until a shelf gets stuck and flips, and of course with loose parts instead of bagged ones.

A row of hanging packages could have a hole shaped like those hanging retail stuff.
So that in the middle position the bag is nicely in a row and then when sided its content is easily available.
« Last Edit: November 24, 2020, 04:45:25 pm by m k »
 

Offline wizard69

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Re: From no parts to decent stockpile, best approach?
« Reply #247 on: November 30, 2020, 07:41:32 am »
Hi, yes I want a a small bag of PCB common components
And have to buy a million of each ... when you find out let me know I’ll keep looking and reciprocate
Many thanks !!
You don’t need to buy a million, just look for electronics parts kits or assortments.   It is better to buy the kits that have an itemized list of what you get.   You don’t want a random box of stuff sweep up from the pick and place machine. 

For somethings, resistors come to mind, it can be very worthwhile to buy in bulk.  However you need to know a bit about your interests and have a bit of experience under you help. For example if you are working with LEDs a lot buying biasing resistors in bulk might make sense.  If you are working a lot with integrated circuits buying bypass compactors in bulk might make sense.  It just saves time for future projects.  Another example here is LEDs which can be very handy to have on hand in a few colors. 

However for the most part I don’t see a lot of wisdom buying odd stuff just to have them on hand.   It wastes money and may never get used past the last project.  Further somethings like electrolytics can go bad on the shelf.  An example here might be a barometric pressure sensor, is it really likely you will have more than one project going is short succession for such a chip.   

I think the key is to get smart about what you really need starting out and don’t waste money on excessive parts purchases.  Here is an example of a kit that itemizes what you should get: https://www.amazon.com/Elenco-CK-1000-Basic-Electronic-Parts/dp/B0002HBQHC.  A little pricey and maybe not what you need.  Most importantly to me is the list of contained parts with out looking all over for it. 

Go to SparkFun and you can find other kits to get started with, some under $20 bucks.  These are just two suppliers there are far more to choose from. 
 

Offline pendoric

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Re: From no parts to decent stockpile, best approach?
« Reply #248 on: December 06, 2020, 07:05:46 pm »
I am just going through this very process.

Right up front I made the decision I wanted a fair amount of parts on hand but I am very conscious it is very easy to get buried under a mountain of parts (and still not have what you want).

I also decided it was worth a few $$ to get the parts quickly and have a place where people have put honest reviews. As such I mainly went with Amazon, they have lots of assortments for very good prices and you can read the reviews for a feel what they are. I think some are knock offs none the less but they get the job done.

Many of these parts came in very similar plastic boxes with small compartments. I decided to buy additional extra boxes rather than stacks of component draws. I also consolidated where it made sense for example 1 put the 1 turn and 10 turn ports in the same little compartment of a single small box. Everything listed below fits in one small milk crate so is pretty wife friendly.

I was mainly looking at breadboarding so the selections reflect that. I will then build SDM via say JCLPCB but may need to rework some things. I am also mainly looking at 'fun' things to do with the tween kids thus microphones and speakers etc but some of the more 'misc' items may not be needed in most cases.

Here is what I started with:

Storage Boxes (actually match most 'kits')
https://www.amazon.com/gp/product/B085RWQKLN
https://www.amazon.com/gp/product/B085RXNNBV

Basics and Passives
Resistors (Best buy of the list)  https://www.amazon.com/gp/product/B08BNDL6DS
Diodes https://www.amazon.com/gp/product/B07Q5FZR7X
Zener Diodes https://www.amazon.com/gp/product/B07BTWBXJ3
Inductors https://www.amazon.com/gp/product/B07CKF43VF
Ceramic Caps https://www.amazon.com/gp/product/B084VMLSFQ
Electrolytic Caps https://www.amazon.com/gp/product/B081PT78Y5
Poly Caps (prob not needed by most) https://www.amazon.com/gp/product/B07G43Z924
10 turn trimmer pots https://www.amazon.com/gp/product/B01N3CJ1QJ
1 turn trimmer pots  https://www.amazon.com/gp/product/B07Z657PQW
Trimmer Caps https://www.amazon.com/gp/product/B06Y4MP4JM

Active / IC / Transistors
BJT Transistors https://www.amazon.com/gp/product/B07TV9FFFQ
MOSFET Transistors https://www.amazon.com/gp/product/B082J3F8HJ
74 Series IC https://www.amazon.com/gp/product/B08281B1YC
IC Assortment https://www.amazon.com/gp/product/B07V1PKDZS
Logic Level Converters https://www.amazon.com/gp/product/B06XWVZHZJ

Misc Mechanicals etc
Bread Boards https://www.amazon.com/gp/product/B01EV6LJ7G/
Hookup wire for breadboard https://www.amazon.com/gp/product/B07TX6BX47
Connectors / Crimper https://www.amazon.com/gp/product/B07ZHB4BBY
Mosfet heat sinks https://www.amazon.com/gp/product/B07FY4RSM8
Misc heat sinks https://www.amazon.com/gp/product/B07PMWGYPV
Foam for expensive IC storage https://www.amazon.com/gp/product/B071G74PGW
9V leads https://www.amazon.com/gp/product/B06X8YZJ64
Misc Battery packs https://www.amazon.com/gp/product/B07BNMKNQX
Mini Speakers https://www.amazon.com/gp/product/B0177ABRQ6
Microphones https://www.amazon.com/gp/product/B01N0VMN9P
8 segment display https://www.amazon.com/gp/product/B01FDD4FRC

Component Kits (Provides things like breadboard wire, switches, leds, photo sensors, cables etc)
Elegoo breadboard kit https://www.amazon.com/gp/product/B01ERPEMAC
SMD Kit https://www.amazon.com/Component-Assortment-Capacitor-Transistor-Soldering/dp/B07GMRJC1Q

I also have a hand full of Pi and Arduino boards I will integrate with.

Even here is the heart of Silicon Valley good electronics supply shops are going the way of the Dodo.  But I do still have one good one left. If you are in the SF Bay area and need something check out.

Anchor Electronics https://anchor-electronics.com/

I still need to find something for crystals and NP0 caps for clock circuits but I will just grab them as needed from Anchor I think.
I also need some higher wattage resistors....

Umm, I see the mountain building...






 
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Offline Distinctly Average

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Re: From no parts to decent stockpile, best approach?
« Reply #249 on: December 27, 2020, 09:15:53 pm »
Some superb tips here. I am not new to electronics, but have taken a very long break. I got into electronics at a very young age getting my first mains shock at about 8. As a student I was repairing TVs, Videos, CB radios (you can date it from that a,one) etc to support myself. I also had other hobbies, photography, windsurfing, cycling as well as study all taking up my time. Later on, marriage and kids almost killed off electronics. Most of my stock I got rid of to make room for children’s stuff. I have tools left, and recently got hold of a decent digital scope and bench PSU. I’ve been dabbling with Arduino and making it do stuff with LED strips etc, and have just begun building some bass guitar pedals for a friend. As such I have really begun getting back into it. This thread has been very helpful in that. So many thanks for all those who have contributed.
 


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