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1  Community / Bar Sport / Re: Your latest purchase on: November 08, 2011, 12:54:22 am
Damn it, gun people all I have is a 6mm electric BB gun smiley-sad

(SRC G36 mod, M120 spring, 11.4v lipo, 900 rpm, breaking MOSFET) fun stuff.
2  Community / Bar Sport / Re: Your latest purchase on: November 07, 2011, 12:28:37 pm
I am making a SAD lightbox double as a general soldering light with remote control here is the LEDs.
http://www.ebay.co.uk/itm/220408382035?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
In theory it should make at least 8000-9000 lumen within the 40° beam angle ....

LED remote control: Suppose to be for coloured LED but it will let me select the number of roll to be lite.
http://www.ebay.co.uk/itm/170691140029?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Perspex mirror as reflector, easy to drill holes:
http://www.ebay.co.uk/itm/180579898692?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Large project boxes can be expensive so I will use A4 size really useful box, the cloudy while cover will double as a diffuser:
http://www.ebay.co.uk/itm/Really-Useful-4Ltr-Box-Fits-A4-Paper-Clear-Pack-5-/260659252266?pt=UK_BOI_Office_Equipment_Supplies_Office_Equipment_ET&hash=item3cb0808c2a

Also 4 18650 Li-ion batteries for messing around with:
http://www.ebay.co.uk/itm/180742201960?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
3  Using Arduino / General Electronics / Re: Preferred circuit layout for running LEDs from transistors on: November 03, 2011, 12:00:43 pm
I have 2 links that you may find useful. It is a LED wizard calculates the values of resistor needed to operate LED in series(s).  Turns out, if you have them in series it actually draw less power than individual with resistor. I think pushing the LED to 200ma is a bit much, it will shorten is life. Most 100ma LED has a peak current at 150mA for pulsing.

http://led.linear1.org/led.wiz
http://ledcalc.com/

use both wizard to compare results.
4  Using Arduino / General Electronics / Re: Voltage regulators on: October 29, 2011, 01:19:45 pm
Quote
I sometimes wires a 7805 on breadboard without caps and they works fine,
Rubbish. Unless by working fine you mean at just one current and you haven't bothered to check the waveform with a scope.
[/quote]

i.e. breadboard, quick test circuit, my point is that it should not damage the 7805 without the caps.
5  Using Arduino / General Electronics / Re: Voltage regulators on: October 29, 2011, 12:40:03 pm
I sometimes wires a 7805 on breadboard without caps and they works fine, there is no reason being damage without caps.

What I am wondering is may be:
1: you may have it wrong way round?
2: is it ground or negative voltage from the transformer?
3: One of them is not a 7805 and different pinout?
6  Using Arduino / General Electronics / Re: Push / Pull Driver ? on: October 29, 2011, 10:54:39 am
There is a IC that can give you -5v with only 2 capacitors. ICL7660/MAX1044. You will need a 7805 to convert that 15v to 5v for its input. It can only handle 100mA.
pdfserv.maxim-ic.com/en/ds/ICL7660-MAX1044.pdf
7  Using Arduino / Project Guidance / Re: DC Auto-Iris control for CCTV lens on: October 28, 2011, 02:35:49 pm
Just checked camera spec, it has AGC, damn it.
8  Using Arduino / Project Guidance / Re: DC Auto-Iris control for CCTV lens on: October 28, 2011, 01:27:13 pm
It is a simple board camera and I doubt it has AGC. What do you mean by nudge loop?
9  Using Arduino / Project Guidance / Re: DC Auto-Iris control for CCTV lens on: October 28, 2011, 12:23:55 pm
Generating a pwm will be to control the opening and close of iris but I want it to automatically responce to the brightness of the video signal, like too bright then close the iris more etc

I can send the video signal through a low-pass filter cut off at around 2MHz-2.5Mhz to extract the lumanace signal and using that to feed to the control mechanism. It is that control machanism that I want to know how to use the camping signal to feedback to the drive signal.
10  Using Arduino / Project Guidance / Re: DC Auto-Iris control for CCTV lens on: October 28, 2011, 10:56:43 am
Anyone?
11  Using Arduino / Project Guidance / Re: Cutting rectangles in plastic enclosures; which tools to diy? on: October 27, 2011, 02:01:56 pm
Diamond Cutting Disc like this is very handy, they are inexpensive can be use on rotary tool or drill. I use them to cut stripboards also.
http://www.toolsdiy.co.uk/shop/view/hobby/mini-drilling-small-files/6pc-diamond-cutting-disc-set/
12  Using Arduino / Project Guidance / DC Auto-Iris control for CCTV lens on: October 27, 2011, 01:07:29 pm
Hi,

I am looking to build a circuit to control the iris of a cctv lens. The input of that lens is a DC auto-iris type which is: pin 1: Damping- , pin2 Dampining+, pin3 Drive+, Pin4 Drive-.
Here is a link on how dc auto-iris work http://www.gevicam.com/images/ED-_TN-07001AI_lens.pdf
I can make a circuit to control the iris manually but it is not practical adjust it for all lighting conditions.
Generally, CCTV uses the output of the video signal to adjust the iris opening size. How do I go about building such circuit for auto-light balancing?

This is part of my other project to use Arduino to control a manual zoom lens. I know how I can attach and control the zoom with servos but the iris part seems to cause me problems.
13  Topics / Robotics / FYI: P5 Dataglove on: October 24, 2011, 02:10:19 pm
FYI: I just found a relatively inexpensive dataglove
http://www.cwonline.com/store/view_product.asp?Product=1179
$59, not bad indeed.
I don't know how accurate it is but in case some of you looking for a alternative method of controlling robots.
14  Using Arduino / Project Guidance / Re: Finished my prototype. What now? on: October 23, 2011, 12:21:27 pm
2 advantage using headers, first you can reuse or replace those chips easy, if you need it on another project later or it gone faulty. Second, some components are sensitive to the level of heat of soldering, so you don't burn your chips.  The larger resistor is higher waltage resistems I think. They can handle more current.
15  Using Arduino / General Electronics / Re: What is a Transistor? on: October 15, 2011, 09:21:11 pm
Are you trolling mate? If not then firstly you will need to understand eletricity then you may understand transistors.  If you don't understand voltage, current, resistance etc then you need to know them first. After that this is a good link for understanding what they do.  http://www.kpsec.freeuk.com/trancirc.htm
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