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1  Topics / Home Automation and Networked Objects / Camera and Galileo on: December 31, 2013, 07:40:19 pm
Hi. I know the Intel Galileo is still relatively new, but does anyone know if you can plug a webcam into it, and access it via an ip address in a web browser attached to the same network?
2  Using Arduino / General Electronics / Re: IR Led on: July 31, 2013, 05:21:32 pm
And you now know the danger of assumptions.
Next time always use at least the next higher available value resistor.

Yep. I'll remember this for next time.
3  Using Arduino / General Electronics / Re: IR Led on: July 31, 2013, 03:53:57 pm
Heh, nope. Down an IR led.
4  Using Arduino / General Electronics / Re: IR Led on: July 31, 2013, 03:35:39 pm
Quote from: RadioShack
Cont. forward current: 150mA
Forward voltage: 1.3V typical, 1.7V max

These are the numbers you're looking for.

I don't know enough about led's to know what that means, so Circuit Playground is telling me to use a 24 2/3 ohm resistor. It would probably be able to run without a resistor then.
5  Using Arduino / General Electronics / IR Led on: July 31, 2013, 03:20:04 pm
Hi. I just bought an IR Emitter rand Detector from Radioshack, http://www.radioshack.com/product/index.jsp?productId=2049723, and it says the emitter is 5V, but that doesn't make sense. I am just wondering what voltage it actually is. Has anyone used these?

Thanks.
6  Using Arduino / Project Guidance / Re: VEX RF Receiver Module Question on: July 17, 2013, 12:08:38 am
I found this, so I am reading on it to see how useful it is: http://www.frank-zhao.com/cache/vex_rx.php
7  Using Arduino / Project Guidance / VEX RF Receiver Module Question on: July 16, 2013, 11:55:15 pm
Hi,

I have a VEX Robotics Receiver Module (Link,) and I was wondering if I can use it with my Arduino Uno R3. I have a few ideas where to start. For one, I know it uses PPM to communicate. I metered it today, and it was getting 5V from the VEX PIC controller. My first guess would be that you would wire the RX directly into one of the Arduino's interrupts.

Thanks to those who can help. smiley
8  Topics / Home Automation and Networked Objects / Question on Scallop Imaging on: July 13, 2013, 10:59:48 pm
Hi. I was wondering if anyone knew how Scallop Imaging takes 5 cameras and combines them in to one stream on-board (Not using an external computer.) I was looking to see if I could do something similar; combine different cameras in to one stream on-board. The cameras would be IP.
9  Using Arduino / General Electronics / Re: Bridge Rectifier on: June 25, 2013, 09:14:19 am
I'm only pulsing the solenoid for 50 milliseconds, so I would think it would be fine.
10  Using Arduino / General Electronics / Re: Bridge Rectifier on: June 24, 2013, 06:45:06 pm
Quote
just attached a 2200μF 50V capacitor on to it, and now it is saying it is outputing just a little less than 40VDC. Does anyone know what it going on here, and if it is safe to attach my 24VDC device to it? (Solenoid and relay)
For a solenoid & relay, don't use the capacitor.

Two things are going on...   The peak voltage of an AC waveform is about 1.4 times the RMS.  The capacitor charges-up to the peak.   Also, transformers are rated at some load.  40VA @ 24VAC is 1.67 Amps.   With a smaller load (higher resistance or no resistance) you'll get a slightly higher voltage.  And, there's some tolerance in that voltage.   (It's one of the main reasons we like to use voltage regulators.)

The RMS voltage is something like an average, and it turns-out that 24VAC RMS (will generate the same power as 24VDC.   For example, here in the U.S. where our line voltage is 120V, the peak is 160V. And if you connect a 100W light bulb to 120VDC, it will glow with the same brightness as 120VAC.     

And, when you rectify AC (ignoring the diode drop) you get the same RMS value.

There is a small difference with a solenoid or relay coil, since they both have inductive reactance, but at 50 or 60Hz, they will usually work fine with rectified AC.

Alright, good to know. I will cut the capacitor off and try it, thanks.
11  Using Arduino / General Electronics / Re: Bridge Rectifier on: June 24, 2013, 06:07:33 pm
I just attached a 2200μF 50V capacitor on to it, and now it is saying it is outputing just a little less than 40VDC. Does anyone know what it going on here, and if it is safe to attach my 24VDC device to it? (Solenoid and relay)
12  Using Arduino / General Electronics / Re: Bridge Rectifier on: June 24, 2013, 05:38:41 pm
It works great, and it outputs exactly 24VDC according to my meter. Now I need to find a capacitor.
13  Using Arduino / General Electronics / Re: Bridge Rectifier on: June 24, 2013, 05:13:03 pm
A drawback of the classic four-diode rectifier bridge is the unavoidable forward voltage drop (Vf) of two diodes when current is flowing.

In my case, it shouldn't be a problem. The two diode together would be about 1V loss. I metered the power supply unloaded, and it was about 25.6VAC, and I need 24VDC, +/- 10% at 0.125A-0.35A.

I think I am going to solder my four diodes together and hook it up to AC, and then figure out the capacitor from there. 22000μF does seem like it is to much, so I will try to find a diode with maybe less than 4000.
14  Using Arduino / General Electronics / Re: Bridge Rectifier on: June 24, 2013, 04:35:07 pm
Looking at the circuit board, the diodes were used as a bridge rectifier. What the board was used for, I don't know. It looks like it has 18VAC going through a 5A fuse before it goes in to the rectifier.
15  Using Arduino / General Electronics / Re: Bridge Rectifier on: June 24, 2013, 04:27:14 pm
Looking up the part number of the diode, it looks to be a low forward voltage (Less voltage loss is how I understand it (0.48V loss to be exact)) and it looks like it should work. I think the board I took it from was actually using it as a bridge rectifier, but I'll have to check on that.
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