power supply (48V) for dual jfet mic pre

buschfsu

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Dec 31, 2004
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jacksonville FL
does this sound ok...

use International Power Linear Power Supply +48V 0.5A PWR SPLY

this power supply (48v regulated) split parallel between the two phantom power suplly inputs on two separate channels of hamptone jfet and a step down power transformer (2:1) to get me to 24V regulated and take that parallel to the circuit inputs on both jfet mic pres. (do i need any passive components other than the iron?)

I want two channels of hamptone jfet (tape op article) using only one power supply. (the artilce mentions a 24V wall wart and regulators). I don't want to use the wall wart and the 48v regulated supply.

If i have this right the regulated supplies will push 48v and 24v respectivley to both boards but the current draw will increase, hopefully not more than the rated 0.5A?

this is going into a 2u case.
 

Svart

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Atlanta GA USA
won't work.

You can't use transformers to modify DC.

Well.. not easily anyway.

Better off using a 20-22v trafo, a voltage doubler, rectifier, 24v Vreg, lm317 and some resistors and caps to make your own supply. cheaper than the one you want to buy and gives all the outputs you need.
 

Svart

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yes that will work fine. you shouldn't worry much about that L, you can do without.

the tl783 is now becomming rare I believe. you can modify the circuit for the lm317HT and it will work fine. Look at SSLtech's 9k PSU for what you need to do for the 48v.

make sure your trafo is sufficiently large, likely 35VA or more.

Where are you located? If you are in the USA you can get nice toroids from Digikey at 35 or 50VA that will be plenty.

good luck!
 

Svart

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Atlanta GA USA
TE62075-ND digikey 16.83$ toroid trafo. I use this one all the time.

That looks like the 783 alright.. i must be thinking of something else not being produced anymore.. :oops:

good luck! :thumb:
 

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