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[Reply #555 on:]

I was getting nowhere using an Arduino with Ethernet for my "Internet of Things" projects and ordered a Pi simply because they were so cheap. After I played around with it for a few days I realized it was a computer, not a micro controller and was the perfect solution to combining sensors and web pages so that I could use my iPhone as the GUI without having to write any apps for the phone. I was pretty surprised at the performance of the Pi running what I generally consider desktop applications. I'm still impressed at what you get for $35.

What class memory card do you have on it? If it is class 6 it will be very fast.

[Reply #556 on:]

I was getting nowhere using an Arduino with Ethernet for my "Internet of Things" projects and ordered a Pi simply because they were so cheap. After I played around with it for a few days I realized it was a computer, not a micro controller and was the perfect solution to combining sensors and web pages so that I could use my iPhone as the GUI without having to write any apps for the phone. I was pretty surprised at the performance of the Pi running what I generally consider desktop applications. I'm still impressed at what you get for $35.

What class memory card do you have on it? If it is class 6 it will be very fast.

Yes, class 6. Best Buy had 8GB cards for $10. I bought several.

[Reply #557 on:]

20 x MAX7219 multiplexing display-things.



$9.60 from eBay including shipping.

I tested one at random (the missing one in the photo) and it worked fine. Note the nice packing.

[Reply #558 on:]

20 x MAX7219 multiplexing display-things.
I tested one at random (the missing one in the photo) and it worked fine. Note the nice packing.

SWEET!  Wow, the shipping to Oz from Shenzen is fast, huh?  I am expecting that my order will still be another few days to arrive.  Yeah, they do tend to be no-frills packing, but these guys I use for price and not for fluff and pretty stuff.  

I really have no idea how they maintain the prices that they do, between them and another similar vendor, I just can't find a fault except for shipping times from overseas.  Beyond that, I swear the prices on half of it won't even cover the shipping cost, never mind the items themselves.  I don't even see how this could be profitable if they were knockoff chips-- you still have to make a knockoff chip that works, or you aren't going to sell many.  All I can think is that they buy whole warehouses of surplus and blow it out.  One tip off that this may be the case is that some times they will have the same device with multiple prices.. In other words, they think in terms of bins, not products.  Two identical products from two different wholesale purchases with a standardized markup.. Employees only know them as bins number 013345 and 547758, or something.

Their employees don't know anything about the products from what I can tell, I had a fruitless and frustrating time trying to let them know that they had made a mistake in their listings (http://www.ebay.com/itm/10PCS-LM2596-DC-DC-Step-Down-CC-CV-Adjustable-Module-Output-DC-1-5V-35V-/400417999181?pt=LH_DefaultDomain_0&hash=item5d3ac5c94d) calling these Voltage regulator modules "CC-CV" when they are not constant current devices.  They were polite enough, but between the language barrier and not understanding the product, it was pointless.  If anyone can send them a note in Chinese explaining, maybe they will fix the listing, until then, just have to know better.  Caveat Emptor, as always- even when the vendor isn't trying to stiff you, unless you are a smart consumer, you still might not get what you think...

[Reply #559 on:]

FTDI breakout module:

http://dx.com/p/ftdi-basic-breakout-arduino-usb-to-ttl-upload-tool-for-mwc-black-142041

Lefty

[Reply #560 on:]

SWEET!  Wow, the shipping to Oz from Shenzen is fast, huh?

Yep, I ordered on 13 March, it arrived on 22 March.

[Reply #561 on:]

SWEET!  Wow, the shipping to Oz from Shenzen is fast, huh?

Yep, I ordered on 13 March, it arrived on 22 March.

Not bad, but I'm a whole lot further way and my Asian E-bay purchases usually get here in 10 or 11 days like clock work, so not much difference.

Lefty

[Reply #562 on:]

SWEET!  Wow, the shipping to Oz from Shenzen is fast, huh?

Yep, I ordered on 13 March, it arrived on 22 March.

Not bad, but I'm a whole lot further way and my Asian E-bay purchases usually get here in 10 or 11 days like clock work, so not much difference.

Lefty

Just a few more days to here except for the bubble-bags that won free trips to Philadelphia. One got 1st prize and spent a week, the other got second prize -- two weeks!
Well, okay, I borrow from W.C. Fields but the timing is more or less what happened.

[Reply #563 on:]

20 x MAX7219 multiplexing display-things.



$9.60 from eBay including shipping.

I tested one at random (the missing one in the photo) and it worked fine. Note the nice packing.

I have had great luck with 7219s from eBay despite being incredibly cheap.  Also, EPM240s.  $1.60 on eBay for qty 50 including shipping or $2.20 each for qty 10 including shipping.  $6.60 each at Digikey.

[Reply #564 on:]

Digikey may be more expensive yet if I order before 3pm, even with inexpensive USPS shipping, I get the parts the next day. Time value of money and a that. Can't beat Asian prices for many components if you're willing to wait, however.

I do wonder how many of them are fakes and / or pulls from existing assemblies but I have yet to have a bad experience with parts / assemblies from Chinese or other resellers. 

[Reply #565 on:]

Digikey may be more expensive yet if I order before 3pm, even with inexpensive USPS shipping, I get the parts the next day. Time value of money and a that. Can't beat Asian prices for many components if you're willing to wait, however.

I do wonder how many of them are fakes and / or pulls from existing assemblies but I have yet to have a bad experience with parts / assemblies from Chinese or other resellers.  

Totally agree.   I just received 5 XMEGAs I want to play with from Digikey today.  No real price advange on these on eBay and I would be waiting 3 weeks instead of 2 days, plus the eBay sellers are selling the A, not the A1 of this chip and I don't know a lot about XMEGAs except the first revs had some bugs so these older codes might not be the best thing to work with.  Minnesota to Chicagoland almost always takes 48 hours which is fine with me.  They generally only charge me about $3 for shipping when I buy a few chips.

[Reply #566 on:]

I did, I hit it out of the park with that synchro meter.  Arrived today, sealed factory packaging.

Emailed the company, as these have to be ordered directly from the company, usually.  First email was simply asking for a price quote for the device, here is the reply:

"The 801-F30 is our standard Synchro/Resolver panel meter with 0.01 degrees of resolution and 0.03 degrees of accuracy. In qty 1-4 pcs the per unit sell price is $2,550 with a 4 week leadtime."

I have now sent back an email explaining that I have one in hand, the project that I am doing, and the fact that I am trying to flip it for the most money I can so I can further finance the safety valve project.  I figure it can't hurt, I have nothing to lose. Worst case the guy tell me to get bent and I sell it on ebay.  I'd be happy to get a reasonable offer to purchase it (so they could recertify and sell), or I figure given the "good cause" nature of my project, he might be able to direct me to the maximum I might get for it.  They sell on ebay USED for $800-$1200.

         

The fates want this valve built too, it seems!

[Reply #567 on:]

Worst case the guy tell me to get bent and I sell it on ebay.

Haha, no the worst case is the guy will tell you it's stolen and you should send it to them.

Back in the old days we used synchronous resolvers to generate sine theta and cosine theta and their multiples to compute various analog functions. Too bad it didn't come with a couple of resolvers. Still, a pretty neat toy.

[Reply #568 on:]

Worst case the guy tell me to get bent and I sell it on ebay.

Haha, no the worst case is the guy will tell you it's stolen and you should send it to them.

Back in the old days we used synchronous resolvers to generate sine theta and cosine theta and their multiples to compute various analog functions. Too bad it didn't come with a couple of resolvers. Still, a pretty neat toy.

LOL, if the guy asks you for it's serial number better hang up. 

Lefty

[Reply #569 on:]

This 8-digit display based on the MAX7219 chip on eBay for $10:



It makes a nice neat package, and is designed that you can put them together horizontally or vertically.


The chip is on the back, out of the way:




I managed to solder on the SMD capacitors and resistor:



You know what? I'm worried if I sneeze I'll never see them again.

Plus, they are the devil to solder. You have to clamp them down or they just wander off.