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Topic: Your latest purchase (Read 115 times) previous topic - next topic

Osgeld

eh i dunno in single quantities I spent 2.90 for a socket, 52 cents on a level shifter, + board + time + header

GoForSmoke

Hey I -have- the SD modules. They did cost me $2.60 each though shipping on the total $48 order did run almost $2. What are the chances that China subsidizes electronics, like they do solar panels?


I find it harder to express logic in English than in Code.
Sometimes an example says more than many times as many words.

Osgeld

its not a matter of being subsidized, its a matter of bulk

just order 10 of something save 30 cents a unit, now order 100,000 of them ...

GoForSmoke

#403
Nov 27, 2012, 10:23 am Last Edit: Nov 27, 2012, 10:30 am by GoForSmoke Reason: 1
And when you make things in 100x previous quantities, it is possible to include tricks that radically cut the cost to make them. I know this for a fact having "been there, done it, wrote the cost estimation and bidding packages" back when I was a production engineer in the 80's.

I say possible because I'm not there. They may be clearing out a lot of items they don't want to continue or just made too many of and want to clear warehouse space. That would also be economical.

Maybe Dealextreme made a mistake and sold these at a loss? Ever find something mis-marked at a big store? Usually luck like that happens when my pockets aren't full, but I've scored before!
Or not a mistake? China LC Tech never asked what *I* paid, just blanket-stated they could beat the cost.

So for me and you where we are is kind of the same boat. But hey man! You want links? Maybe get some yourself?

http://dx.com/s/sd+module.html?range=ShortHeadLine1&category=499&GEPrice=1.00&LEPrice=4.00
I got the 3rd one, it's $3.20 in single but I bought 3. Catch is when you order "bulk" (more than 1) you have almost $2 shipping for the whole order instead of free shipping.
http://dx.com/p/sd-card-module-slot-socket-reader-for-arduino-arm-mcu-133709

http://dx.com/c/electrical-tools-499/diy-parts-components-410
This is the whole DIY selection, note the BT module for $6.60 in single, $5.48 ea at 10.

And I got docs. The only one I couldn't have found is the module schematic showing the LM1117-3.3 between the 5V and 3.3V pins. Other than that, I might need to run at 3.3V or level shift MOSI, MISO, SCK and CS.... I need help to be sure. Man, that could ruin the "quick, clean and easy" part of this nutritious breakfast!

The rest of the docs are generic SD card and SPI specs. I will share if you want.

You do know there's info in the Playground to solder wires to an SD adapter (the kind you often get with micro-SD cards) and run directly from that (must be 3.3V levels). It's not elegant or quick and clean but to a guy with your skills I guess easy is still on the list.  ;)

Edit:
Looking more at the schematic, I see where the signal lines all connect to 3.3V through 10k resistors. I am puzzled, perhaps 5V signal loses kick through the resistors while the same don't allow enough 3.3V through to give logic level ON? For all I know, I'm looking at a level-shifter, I don't know hardware beyond the rank amateur level.
I find it harder to express logic in English than in Code.
Sometimes an example says more than many times as many words.

draythomp

I've bought a number of items from China and yes (almost) they subsidize shipping.  Most of the stuff come with free shipping.
Trying to keep my house under control http://www.desert-home.com/

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