Your latest purchase

Maybe the time to fill a big R-C circuit both without and with that resistor would show something? But that would depend on how steady the power going in would be.

I tried again with a firmer connection to the resistor and doing a Kelvin measurement. Still got 8.8 mV with 4A going through it, so out by a factor of 2 as far as I can see.

A quick appraisal of my online electronics purchasing experience to date:

sparkfun.com: good product descriptions, reliable stock levels, quick feedback due to credit card processing being broken, but then fixed a day or so later. Good notification and delivered in a week. Sparkfun's packing department are incredible.
futurlec.com: order still not shipped after 2 weeks. replied to email enquiry within a day to say 7 items from my order are out of stock and will not be in stock for 1-2 weeks, when my order will be dispatched. website currently lists all 7 items as in stock.
dx.com: charged my credit card twice for the order. has apparently dispatched 3 shipments making up the complete order, but so far nothing has arrived (10 days since first shipment notification).

2 x ebay sellers (1 China, 1 Aussie) have shipped products asap and received them within a week.
Another ebay seller has shipped but via cheap shipping (US), so still waiting for the order to arrive (10 days and counting).

I remember a place in Australia called Dontronics that had a scheme called Simstick. I liked the idea of putting chips on like-memory cards in a small bus.
I did get a dev board for AVR 90Sxxxx chips from them but RL stepped in and next thing I knew Arduino was available.

Does anyone Down Under know Dontronics? I do wonder how many places like that there are in Australia and how good a country it is to run a small to medium business out of?

Never heard of them, so checked them out. Interesting site. Can't really tell what they're selling though. Layout is not the easiest to follow after sparkfun spoiling me with pics and descriptions.

Electronics SME in Australia not that great, imo. Market is tiny, international postage costs are steep, shipping components in can be expensive. If I had a good idea that would sell, I'd probably go to the US to do it first.

Love the place though, wouldn't trade it for anywhere else.

Got another order in with Yourduino.
Note that the chips and thermistors are package of 5 for from 75 cents to $1.50.

Order Summary:
Product
Qty Price Subtotal

2.4GHz Transceiver Low Power nRF24L01+
2 $2.75 $5.50

AC Line Power Supply: 9V 1A
2 $3.00 $6.00

AC Line Power Supply: 3.3VDC 2.5A
1 $4.50 $4.50

5.5mm x 2.1mm Plug for Arduino External Power Connector
4 $0.35 $1.40

LM324 4x opamp (single supply) (Pkg of 5)
2 $0.75 $1.50

LM386 Audio amp low-voltage (Pkg of 5)
2 $0.75 $1.50

NE5532 Low Noise Dual Op Amp (Pkg of 5)
1 $1.50 $1.50

74HC165 8x Parallel-In Serial-Out Shift Register (Pkg of 5)
1 $1.50 $1.50

Thermistor 10K (5ea)
1 $1.25 $1.25

AC Line Power Supply: 5V 1A
1 $2.50 $2.50

Subtotal: $27.15
Shipping: $15.00
Tax: $0.00
Total: $42.15

GoForSmoke:
Got another order in with Yourduino.

What's their stock level / shipping time like?

Last time it was about 2 weeks when I expected 3.
I paid $3 extra for Fedex and figure less than 2 weeks.
What I don't know is about parts in stock.
DX hung me up twice out of 5 orders on stock. Both times there were big holidays in China.

For me the wait is not a big deal. Getting my parts is and so far I've always gotten my parts. Next down the list is parts being what I thought and for 3 particular parts out of many I ordered too quick from DX where the lack of info can equal or exceed the clear info.

Last of all, I did buy cheap ($2) hand-crank cell phone chargers from DX that are jokes. They have a wondrously inefficient set of plastic gears to drive a tiny motor/generator that does a great job of lighting the power led with moderate effort but 5V requires major effort. I might try one if it was an emergency and I was stuck. Caveat Emptor! I could probably do better putting a crank on a stepper motor or something.

3 old purchases just gave me 6 good size super magnets. :smiley: They make the super field that the voice coil moves across strong and precise enough for the HD to work back when it did. That's one kick@$$ field, it's got an arc shaped magnet above and one below. Want to build a strong generator or motor? These are worth a few bucks each.

These are bad HD's from back in the 90's. It takes a bit of work and a set of small torx drivers but hmmmm-ha these are IMO worth it.

One thing; case labels and warranty stickers usually cover a couple of screws that if you find them and get them off then you won't need a pry bar or claw hammer to get the damn lid off!

The platters are nice too. They'd make nice Tesla Turbine disks.

A medium sized cardboard box stuffed with new old stock archer / radio shack parts for 5 bucks at the thrift store!

GoForSmoke:
The platters are nice too. They'd make nice Tesla Turbine disks.

Or frisbees. In high school we had a Vax 750/11 with a RL02 removable hard disk drive, among other, refrigerator-sized attachments. These RL02 discs crashed often, and we'd scavenge the insides of the carrier for the platters and play frisbee with them. At about 14" across and heavy, good palm protection was a must, as was good aim. Otherwise, you'd be at risk of a 'oddjob' re-enactment.

In terms of disk platters, Richard Stallman (the guy who created the Free Software Foundation, Emacs, and GCC) came to last year's Gnu Cauldren in Prague for the 25th anniversary of the creation of GCC), and after talking about serious issues in terms of keeping software free, he donned his robes as Saint IGNUcius, and his halo in a former life was a disk platter:

GoForSmoke:
The platters are nice too. They'd make nice Tesla Turbine disks.

Just make sure you don't get one of the ones that use coated glass/ceramic platters!

"Weird Stuff Warehouse" recently acquired a load 12inch laser-disks, and I bought one ($1 each!) just to add to my "collection of obsolete media."

Atmel Capacitive Touch Sensors , these are the one channel , i also purchased a couple 7 Channel .

aarondc:

GoForSmoke:
Got another order in with Yourduino.

What's their stock level / shipping time like?

Box got in after spending time playing tag with Fedex. From order to arrival worked out to 4 days on a 3 to 6 day shipping method.

Everything arrived in good shape in a sealed & bubble-padded package.

I'm set for a while except maybe I want more of those 5/$1 RGB leds and shift registers to drive them with, or maybe I want analog led drivers.....

Thanks for the follow up, GoForSmoke.

Ordered a bunch more stuff from dx.com and sparkfun.com. futurlec.com might be less-dodgy looking than dx, but dx.com deliver quicker and have good prices, their kit works, and they refunded the second debit they put on my card within the week they estimated it would take to do so. Been three weeks since I placed my futurlec.com order and it still has not been sent. All the items they listed in their email as out of stock when I queried them were still listed as IN STOCK on the site. Meh.

DX have shipped a large order in 3 separate lots in the same time. Sparkfun will have shipped 2 orders separated by 3 weeks before the futurelec.com order arrives. It's been a good lesson for me if I ever manage to come up with a product people want to buy and I want to sell. New SFE order was for some headers and what not but more importantly, a Makerbeam kit. Gotta love free shipping - that's $140 cheaper than it was the week before.

Managed to interface most things from my last dx/SFE orders last week, which has been a good learning experience: GPS, bluetooth, USB port, RF remote control and RF transceivers, as well as some other bits and pieces like LED units. My new DX order was essentially some more of the above, as well as some headers and other bits and pieces.

Pointers are my Achilles heel in C, so I bought the kindle version of this last night:

I have been researching FPGA devices, and decided on VHDL as the language I want to learn. Very few of the FPGA books are available electronically, so was pleased to find the kindle version of this last night, after reading some good reviews on amazon:

And to help me learn VHDL, I lashed out and got one of these off Ebay ($182 with free postage):

I'll turn to the FPGA book and board when my Arduino projects start bogging down or I need a break.

aarondc:
And to help me learn VHDL, I lashed out and got one of these off Ebay ($182 with free postage):

I'll turn to the FPGA book and board when my Arduino projects start bogging down or I need a break.

Last summer I got this board from Terasic, using an oldish student card:

Very good deal. It's been fun to mess with and throw Verilog against to try stuff out. The chip is HUGE. I see your board is this one after a little bit of searching:

http://www.ebay.com/itm/ALTERA-FPGA-NIOS-CYCLONE-IV-EP4CE15-USB-BLASTER-Power-Adapter-Many-Gift-E082-/261058354313

If you have a student card, the Terasic board is a great deal, 115K LEs as opposed to 15K LEs, but I suppose that doesn't matter until you need them. Even 15K is a lot compared to CPLDs.

JoeN:

aarondc:
And to help me learn VHDL, I lashed out and got one of these off Ebay ($182 with free postage):

I'll turn to the FPGA book and board when my Arduino projects start bogging down or I need a break.

Last summer I got this board from Terasic, using an oldish student card:

Terasic - All FPGA Boards - Cyclone IV - Altera DE2-115 Development and Education Board

Very good deal. I guess it is similar to yours. It's been fun to mess with and throw Verilog against to try stuff out. The chip is HUGE.

I spent some time working out if I could get a uni friend to get one for me - given I have not been a uni student for a while, and in the end decided The cheaper board was less hassle. Those DE2-115s look unreal though. If I had a student card it would have been a no brainer.