DIY Mic Pre Kits, Lunchbox Mic Preamp Kits, Power Supply Kits

Hi, First thank you Ruel, i bought a couple things from you, you have top notch quality and service! :D im very satisfied! thank you for all you do for us!


I just have a couple question to get the thing going:





How would i add a power led for the pm1000 power supply?

I know its different than the sc-1, im still green about these things
and i havent found any clear info.



Also, using your kit , how do i connect the different pm1000 module?

In parrallel I guess? meaning the two module + connect to the same point
on the psu?




The info on your site is realy helping, just these point im not sure

Thanks for taking the time to answer, i know its a very basic questions
but im still try to learn and the pm1000 is my first non battery projects.



John

Hey John..



Determine the current requirement of your LED, I.. .. 5mA, 10mA or 20mA... then compute for Resistance R using Ohm's law, R = E/I
E is the voltage. This will be the current limiting resistor for the LED. Otherwise, you're going to burn up and destroy your LED.

Compute for power rating of resistor P = E x I. Pick the higher rating avaialble... 1/4w, 1/2w, 1watt. Otherwise, your resistor could become hot.

Adjust R to higher value (or get the next higher value) if you want to dim the LED brightness.




Yes. Connect them in parallel.

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thank you very much for trying to help me, but im still very confused.
this is a little too deep for me, (im still confusing current and voltage..)

Lets say i want to use the led in your power control kit, i know its 2.1 volt max, but i dont know the current requirement.
what resistor value would i need to limmit the voltage?
Or should i get a bigger led?


Im confused also to where to connect the led,
is it the 44v/48v side?

and where exactly? is it in parallel to the + and - with resistors in serie with the legs.

If you have a picture or you know a good link where i could learn this stuff that would be very useful!

If adding a led as any negative effect on the circuit, i will skip it.

Im sorry for the beginer questions, i hope this topic can help other
people in the future.



thanks

john

John, use a 8.2K resistor in series with the LED, connected to the 44V power. Use a 1/2watt rating resistor. You could also use a 10K, but don't go lower than 8.2K.



(+) ------- Resistor ------ LED --------- (-)

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Thanks Owel,

Now everything is clearer, i feel confident enough to do it!

I will use these formulas for future projects too, im starting to understand!


thanks, keep up the good work, when you become rich you can hire
a tech to do customer service


Thanks again for what you do for the comunity of diy.


John

I forgot one thing:

what about led polarity?
Do i connect the led + side on the 44v + side like this:



+--------resistor----- + led - ------------- -


also, on your led wich is the + side ? the long leg?


thanks


John

Oops... the long leg is the (anode) or (+).

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Ok, thanks, so i take for granted its like that:



44v + ------------- 8.2k resistor--------- " + led - " ----------------- 44v -



I just hope these dumb questions will also help others do pm1000's
Thnaks for your time Owel,

when im finnished, ill post result in the gallery.



john

To be exact, it's labeled GND. (not 44-)

Yup, that should be it.

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