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Old 9th May 2006, 04:03 PM   #101
Ryssen is offline Ryssen  Sweden
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Okay,I go back to where it worked,the original CCS 300v/15mA,worked fine.My idea besides CCS for the Ledīs(Do you have a suggested dessign-NPN-?)was direct coupling,thatīs why the higher voltage 495v.
Will an RC filter be enough to bring the votage down to safe level(300v)or shall I use a SS regulator?



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Old 9th May 2006, 10:49 PM   #102
lndm is offline lndm  Australia
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Do you have a circuit simulator? I have created so much smoke on my computer that by rights I shouldn't be able to read the screen anymore.
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Old 10th May 2006, 12:14 AM   #103
EC8010 is offline EC8010  United Kingdom
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Quote:
Originally posted by Ryssen
My idea besides CCS for the LEDs, (do you have a suggested design - NPN?) was direct coupling, thatīs why the higher voltage 495V.
Will an RC filter be enough to bring the votage down to safe level (300V) or shall I use a SS regulator?
The NPN design is with the others in the earlier thread about CCS PCBs. A correctly-designed RC filter will be adequate to bring the voltage down to <300V (I would suggest 250V).

I repeat that you need to learn more about theory before attempting to modify designs. You can learn about "boring" theory or you can live with "exciting" explosions/smoke and destruction of expensive components. The choice is entirely yours...
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Old 10th May 2006, 07:14 AM   #104
Ryssen is offline Ryssen  Sweden
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Quote:
The NPN design is with the others in the earlier thread about CCS PCBs. A correctly-designed RC filter will be adequate to bring the voltage down to <300V (I would suggest 250V).
Yes I know about the NPN CCS, I will try to implant it into this project of mine.
Quote:
I repeat that you need to learn more about theory before attempting to modify designs. You can learn about "boring" theory or you can live with "exciting" explosions/smoke and destruction of expensive components. The choice is entirely yours...
Yes you are right,I will read more more on the subjects,maybe Iīm just in a hurry to get it done. ....
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Do you have a circuit simulator?
Suggest one.
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Old 10th May 2006, 07:25 AM   #105
arnoldc is offline arnoldc  Philippines
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Simulators -

LT SPice from Switchcad

Simetrix from Cadena

and a couple more...
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Old 10th May 2006, 07:36 AM   #106
lndm is offline lndm  Australia
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CircuitMaker.

Version 6 student edition is free (limited to 50 components at once) if it's still available. I use cm2000.
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Old 10th May 2006, 04:03 PM   #107
Ryssen is offline Ryssen  Sweden
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Ehmm...little OT,trying LT spice,I canīt edit the Led Diode properties-gray field,how.And how do I get the symbol of a triod?Iīll bet it is an easy answer..
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Old 10th May 2006, 11:42 PM   #108
arnoldc is offline arnoldc  Philippines
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hi ryssen,

please visit duncan amps website for the models of the different devices. the site also has instructions for using a tube model.

When you click on Component from the toolbar, you selected a diode and it was labelled D1 D.

Now, insert the model entry for the diode, example 1N4004:

.MODEL D1N4004 D(IS=2.55E-9 RS=0.042 N=1.75 TT=5.76E-6 CJO=1.85E-11
+ VJ=0.75 M=0.333 BV=400 IBV=3.95E-5 )

Copy this text, press S on LT Spice to insert a Spice direcftive. Paste the text.

Then Right Click on the D label of your diode and type D1N4004 into the text box.

That's my OT answer
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Old 11th May 2006, 07:03 AM   #109
arnoldc is offline arnoldc  Philippines
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Back to topic...

Sy, you think I can make a "red light district" PP EL34? I plan to change the cathode resistor of my EL34 PP amp with a bunch of red LEDs 35V / 1.5V = 24 red LEDs?
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Old 11th May 2006, 07:47 AM   #110
lndm is offline lndm  Australia
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I thought of doing this. I baulked when I figured that if I wanted 10mA per LED, for 100mA I would need 10 strings of diodes (I don't have SY's experience here though).
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