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571  Community / Bar Sport / Re: A broken Arduino... on: February 07, 2014, 03:31:02 pm
The chip's a 386?

As in an intel 386? (Tradionally square cpu?)
572  Using Arduino / General Electronics / Re: Are these Shift Registers The Same? on: February 07, 2014, 08:17:21 am
I just searched for the 595 at jaycar and found nothing...

Yet it is included in the startup kit, which makes me think the components in the kit were sourced from overseas like china, in which case buy them from ebay.
573  Using Arduino / General Electronics / Re: Are these Shift Registers The Same? on: February 07, 2014, 05:31:58 am
Just get them from ebay if you want to keep the price down... they work fine mostly. 
574  Using Arduino / General Electronics / Re: Am I a resistor? on: February 07, 2014, 05:28:05 am
I was talking about actual current readings.... the resolution might not be good enough to measure how much current flows with just a couple of volts..
575  Using Arduino / Project Guidance / Re: Android Notification light! on: February 07, 2014, 05:19:04 am
The pro way would be to write an android java service and hook the notification services, then when you get one, the app connects to your arduino (be bluetooth or wifi) and then blink the LED.

A crude way might be to use an LDR to detect light from the screen waking up, or maybe a microphone to listen for sound..

576  Using Arduino / General Electronics / Re: Am I a resistor? on: February 07, 2014, 05:14:44 am
There is still no voltage threshold for material like this. It is just that the ammount of current they conduct is negliable at lower voltages.

Look, when I said that I had a distributor cap in mind, when the contacts fail you can see the path left behind in the plastic...  but that's never going to happen with a few volts...

As far as humans go... what you're saying is if you touch both terminals of a battery (be a 1.5v or 12v) a very low amount of current will flow ... I get it, but to me a threshold value is something were substantial current can flow... but fine your point is made even though most multimeters would not be able to measure how much current flows through your body or maybe they do...

I'll start with 1.5v and see how much current will flow through me (1.5v/500k)..
577  Using Arduino / General Electronics / Re: Am I a resistor? on: February 07, 2014, 03:55:56 am
To an extent, most things are a resistor once the voltage overcomes a threshold for that material.
That is simply not true there is no threshold to overcome. On non linear things like LEDs there are voltage points where the resistance changes but there are no thresholds as such.

i was not talking about semi conductors, electronic components, i was refering to every day materials, wood for example, skin, cotton, they can all conduct if you appy a high enough voltage.
578  Using Arduino / General Electronics / Re: Are these Shift Registers The Same? on: February 07, 2014, 03:30:54 am
In my experience from ebay parts and jaycar...

The ebay clones work just as well... however the clones don't handle higher voltages, for example a 555 bought from jay car was happywith 12v. The 555's off of ebay stopped working over 9-10v likewise for other ics including 7hc595s...

BUT

I'd like to know for sure how to tell if it's a clone or not. (Other than testing all the max specifications to make sure it meets specifications)
579  Using Arduino / General Electronics / Re: Am I a resistor? on: February 07, 2014, 03:23:48 am
To an extent, most things are a resistor once the voltage overcomes a threshold for that material.


Glass , rubber and plastic are the best non conductors.
580  Using Arduino / Programming Questions / Re: Writing a function to read integers from Serial. on: February 07, 2014, 01:39:34 am
I hate questions like that...

You may well say don't use any functions as you did not write them... so you may as well just present back with the theory on how it's done...  as any code used will not entirely be your own!
581  Using Arduino / General Electronics / Re: Current flow + to - on: February 06, 2014, 05:37:17 pm

Thanks for the links...
582  Using Arduino / General Electronics / Current flow + to - on: February 06, 2014, 09:30:10 am
When reading circuits, more specifically let's control an npn.

Via conventional flow you can say, when the base sees 0.6v the transistor begins to conduct.

But, if you imagine the flow from negative to positive, how's the transistor switch on?  As the flow would be leaving the base pin?
583  Using Arduino / General Electronics / Re: Flow of electricity - Simple Circuits on: February 06, 2014, 09:21:14 am
Quote
The physicists, once aware of their basic error invented 'hole flow' so they could continue to believe (in error) that current flows from positive to negative.

I don't even know where to start with how wrong this is.



Which part?

In the past they believed the flow to be from positive to negative.. until it was proven untrue.

584  Using Arduino / Project Guidance / Re: Android Notification light! on: February 05, 2014, 05:24:22 am
You want an external led to blink when you get a notification?
585  Using Arduino / General Electronics / Re: Which Handheld Oscilloscope? on: February 05, 2014, 03:28:10 am
At this point in time, I'd strongly suggest you stay away from pocket and handheld 'scopes. I recently bought a DSO 203 aka DSO Quad, and I'm sending it back. Buggy, false claims of the analog bandwidth, etc.

There are plenty of smaller bench scopes that are very portable with decent specs. Hantek, Rigol, etc. Better to save a bit more than waste your money on junk.

The trick is to upgrade the firmware and use a 3rd party.. that fixed the issues you speak of.
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