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Old 10th February 2010, 06:38 PM   #41
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I think I am using a 1.6A with my 22v 300va. It has been in there for a number of years now. That may suggest it is over rated for my setup. Cricklewood Electronics have everything you will need.

Cricklewood Electronics - CCTV. CCTV Equipment. CCTV Systems. Digital CCTV Cameras

You will see others say you need a soft start, you may be better to keep your options simple to start with.

John
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Old 11th February 2010, 06:24 PM   #42
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This is the LED i intend to use on rectifier board... I have a nice Optic fibre kit that will let me put a blue power light on the front panel.

Can anybody help with what resistor it will need. Transformer is 300VA 2x22v. Dont wanna solder one in to have it blow on me.

http://www.vcclite.com/Customized/Up...VAOL-3GWY4.pdf
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Old 11th February 2010, 06:27 PM   #43
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Here you are: LED calculator for single LEDs
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Old 11th February 2010, 06:35 PM   #44
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So im doing 22v, 3.3v and 30mA.. or do I add the 2x22v and use 44v as voltage... I know i'm a pain, it'll all be over soon.
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Old 11th February 2010, 06:47 PM   #45
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Transformer is rated in AC volts, after rectification you can expect approx 32V DC per rail and that's what you use for calculations. This is what you get:

If you find diode too bright, you can further increase resistance (and that's what I always do). I'm using 64k resistor with a small Panasonic red LED.
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Last edited by Peter Daniel; 11th February 2010 at 06:51 PM.
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Old 11th February 2010, 06:51 PM   #46
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Thank you
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Old 11th February 2010, 06:52 PM   #47
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I adjusted the current for 20mA per datasheet.
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Old 11th February 2010, 09:44 PM   #48
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Quote:
Originally Posted by littlerick View Post
This is the LED i intend to use on rectifier board... I have a nice Optic fibre kit that will let me put a blue power light on the front panel.

Can anybody help with what resistor it will need. Transformer is 300VA 2x22v. Dont wanna solder one in to have it blow on me.

http://www.vcclite.com/Customized/Up...VAOL-3GWY4.pdf
The larger size resistor you use, the dimmer the LED will be. They can be extremely bright so when I'm building guitar pedals, I usually start around 1K-2K and work my way up until it looks about right. Since you are dealing with much different voltage in these power supply boards, you should start with Peters recommendation of 62K and adjust from there. A lower value (say 50K) will make it brighter, a higher value (say 80K) will make it dimmer.

Last edited by captainobvious; 11th February 2010 at 09:46 PM.
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Old 12th February 2010, 04:27 PM   #49
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I have some single solid core wire i have been using in breadboard... Will this be thick enough to use for the dc power from rectifier to amp?

I am currently stripping the rubber from an old pc psu to cover the silver signal wire.. I'm using 0.60mm silver plated copper for the input and outputs, but stripping the rubber is killing me. I know you can buy it, but i'm an unemployed guy so money is tight.

Managed to get some samples of plastic bolts, nuts and washers for fixing amp chip to heatsink so i dont need to worry about shorting it. That said I have no intention of turning it on until i have tested everything at least twice.

Wire info... Overall diameter is 1.2mm, rated at 1.8A, 1kV
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Old 13th February 2010, 03:28 AM   #50
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Yes, it should be fine.
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