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[Reply #450 on:]

The latest package finally arrived from HK! Factory-direct deals. I got my stuff, the experience has been positive.

1 MP3 dev module
1 3-axis gyro module
1 3D magnetic compass module, 1-2 deg accuracy (won't be using it to survey with)
3 SD modules (I got a real good price)
4 ultrasonic range finder modules
2 10A 240VAC relay modules
4 4 digit 7 segment led display modules (uses 7 + 4 pins, but very low cost)
2 BT modules capable of host or slave operation

http://www.lctech-inc.com/Hardware/

Notice no prices listed? Minimal docs? Their business model is just ask. They do PayPal.
My contact: chinalctech@163.com

Just to be clear: I don't work for or have any deal with them except my own prices. I get nothing for or from what anyone else buys. My relation is purely as a hobbyist, I do no sales and get no commissions.
But I see those things and have a small collection, I just have to share especially with others like me who aren't so great at assembling hardware and also the ones who want to save time. All the modules have pins.

[Reply #451 on:]

Jw how much did u pay for some of those thing like the slave,master bluetooth and the sd card slot?

[Reply #452 on:]

They emphasize that the prices I get are -my- prices only. I gave some advice that maybe helped them or showed what they like. Or maybe I was just lucky that day but they will try and beat competition.
The less complicated modules, the things I bought more than 1 of all ran me less than $2 each, the more complicated ones were all under $10 for me. The BT master/slave units were less than $8, I have seen BT units on eBay and DX for less than $7 but I dunno the differences since LC sells BT master and BT slave as well as the dual-units and I can't read Chinese to know what-all the differences are so I ordered the best they make.

You _have_ to ask. That costs sending an email referencing what parts and about how many.

It is the same process of seeking bids and getting replies that business ran by back in the 80's and 90's when I wrote production and cost estimation software. They're not geared towards small quantity purchasers but they welcome us perhaps because hobbyists do come up with uses that may 'go viral' in an industrial scale way.

[Reply #453 on:]

Most of those Asian devices are available from many many Asian sellers on Ebay at I would guess the same price they are selling directly (but without listing their prices, who knows). It's just a matter of searching and comparing the offerings.

Lefty

[Reply #454 on:]

Definitely, always ---- shop!

LC is a place I found with neat toys at good prices, not the second coming!

[Reply #455 on:]

Swift 80 Series Microscope.  10x and 20x magnification.  Got it off Ebay for 50 bucks.  Think I got a pretty good deal.  Been wanting one for soldering those fine pitched ICs that have been stuck in the parts bin for awhile.

[Reply #456 on:]

The BT master/slave units were less than $8, I have seen BT units on eBay and DX for less than $7 but I dunno the differences since LC sells BT master and BT slave as well as the dual-units and I can't read Chinese to know what-all the differences are so I ordered the best they make.

They are programmable from slave to master / etc, or it might be dependent on the firmware as to whether it can be switched. It's the same hardware, at any rate. I recall stumbling across a firmware download for these modules so ... something to look for perhaps.

Stuff to read if you're bored:
http://elecfreaks.com/store/download/datasheet/Bluetooth/HC-0305%20serail%20module%20AT%20commamd%20set%20201104%20revised.pdf
http://www.seeedstudio.com/wiki/index.php?title=Bluetooth_Bee

[Reply #457 on:]

Swift 80 Series Microscope.  10x and 20x magnification.  Got it off Ebay for 50 bucks.  Think I got a pretty good deal.  Been wanting one for soldering those fine pitched ICs that have been stuck in the parts bin for awhile.

Thats a nice looking microscope (though it looks "backwards" to the ones I am use to seeing) ... 50 bucks hunh, crap first I need a bigger bench (still using my card table ... since 2006)

[Reply #458 on:]

Thats a nice looking microscope (though it looks "backwards" to the ones I am use to seeing) ... 50 bucks hunh, crap first I need a bigger bench (still using my card table ... since 2006)

The eye piece rotates 360º.. If that was your meaning..

[Reply #459 on:]

ok now that could be darn handy. the one I use at work I am constantly trying to "twist" the board to inspect it from different angles and the neck of the microscope is always in the way

[Reply #460 on:]

The BT master/slave units were less than $8, I have seen BT units on eBay and DX for less than $7 but I dunno the differences since LC sells BT master and BT slave as well as the dual-units and I can't read Chinese to know what-all the differences are so I ordered the best they make.

They are programmable from slave to master / etc, or it might be dependent on the firmware as to whether it can be switched. It's the same hardware, at any rate. I recall stumbling across a firmware download for these modules so ... something to look for perhaps.

Stuff to read if you're bored:
http://elecfreaks.com/store/download/datasheet/Bluetooth/HC-0305%20serail%20module%20AT%20commamd%20set%20201104%20revised.pdf
http://www.seeedstudio.com/wiki/index.php?title=Bluetooth_Bee

Thanks but I don't want to scarf their bandwidth and take their docs after buying elsewhere that gives me docs. I have used AT commands with modems, long ago. I will try starting there.

I need to start buying at sites that post support just to support the practice of posted support.
Hmmmm, that's got meter to it....

I got an ultrasonic module figured out last night for playtime.
I only had one detour. After I flip the trigger on and off there is a period before the echo pin goes HIGH and stays HIGH until the echo returns. The site description kind of slid around that how long the echo pin takes to start timing.
I shoulda knowed better, once the trigger is hit the rig sends 8 pulses of 40 kHz (it says) which I think the echo pin doesn't go HIGH until the last wave is out. I was testing 400-480 passes through a while loop with a timeout test included. Those times varied by 80 usecs with everything sitting still. Do I need caps across any of those lines perhaps? It's a low power device but so is the Teensy running it.

The round-trip distance formula at 340 m/s comes out 5882 usecs per meter. Temperature (not density) from Standard changes sound speed m/s. Colder is slower.  

[Reply #461 on:]

Not a good photo but a fun watch. The MetaWatch Strata. The firmware is still in its infancy but is still plenty useful with the iPhone 5.

[Reply #462 on:]

Hey everyone, first post here, kind of new to all of this.

We hit the Disabled American Veterans Thrift store yesterday. Brought home:

• Old digital step-on scale
• Old computer keyboard
• CD drive
• PlayStation 2 Multitap
• Playstation 2 controller
• Hooked-on-Phonics handheld game
• 3 RC cars without controllers ($0.45 each)
• Motorized Tractor with a tethered controller

Amazingly, no objection from my wife. Now the question is, what do I do with the stuff? I have a vague idea of what sorts of components I may now have but I don't know how to go about identifying them and removing them. Any tips for a newbie?

I've got myself an Arudino recently, I've burned through the beginners books and some basic tutorials and now I've remembered I don't know how to source electronics components. I'm itching to get at those parts though. Eventually I'd like to work towards exploring Autonomous Underwater Bots which I think could be very useful in my field (Hydrographic Survey). For examples schools of robot "fish" to collect data on water conditions. Just need to get my head around components.

[Reply #463 on:]

I've remembered I don't know how to source electronics components. I'm itching to get at those parts though.

I mostly get what I need from the internet.  But here is a few of the common sites.

http://www.sparkfun.com/
http://www.digikey.com/ - Site has about %99 of the components you will ever need.  Only bad side is digging through all of them.  But it has an excellent filter system.
http://www.mouser.com/ - Pretty much the same as above
http://www.taydaelectronics.com/
http://www.adafruit.com/
And of course Ebay
Locally - Radio Shack (only for those very common parts)

Eventually I'd like to work towards exploring Autonomous Underwater Bots which I think could be very useful in my field (Hydrographic Survey). For examples schools of robot "fish" to collect data on water conditions. Just need to get my head around components.

Search this site, quite a few members doing the same thing.

[Reply #464 on:]

If you limit your selections and buy in bulk (hundreds or thousands), you will find that it is much cheaper to buy from a reputable distributor like digikey, etc.