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Old 13th November 2009, 10:25 PM   #1
wensan is offline wensan  United States
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Default The simplified schematic of J2 what I suppose to be.

Here is the simplified schematic of Firstwatt J2 that published in the owner's manual of J2.
Click the image to open in full size.

It says the output stage current source is no longer an "Aleph" current source, but a version of the classic "Mu Follower".
But the simplified schematic of Firstwatt J2 shown just a basic circuit of SRPP(Shunt Regulate Push-Pull).
Since it claimed to be a Mu Follower,
I suppose the simplified schematic of Firstwatt J2 should be just like this.
Click the image to open in full size.

At first, I guest the regulator IC in the schematic is TL431.
Then the voltage drop of those two resistors will be 2.5V, it seems too high.
So, I guest the regulator IC in the schematic is LM385.

Last edited by wensan; 13th November 2009 at 10:44 PM.
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Old 14th November 2009, 05:13 PM   #2
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That will work, but it is not the J2 voltage source. I am not
planning on making the circuit details public, so I suggest
that you just pick a nice voltage source and go with it.

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Old 15th November 2009, 05:31 AM   #3
wensan is offline wensan  United States
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Quote:
Originally Posted by Nelson Pass View Post
That will work, but it is not the J2 voltage source. I am not
planning on making the circuit details public, so I suggest
that you just pick a nice voltage source and go with it.

Yeah, I knew that will work.
But if I announce this schematic not you,
I think no one will have interest in it.
So sad!
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Old 15th November 2009, 05:58 AM   #4
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Sad for them, but not for you
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Old 15th November 2009, 07:33 AM   #5
wensan is offline wensan  United States
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Quote:
Originally Posted by thanh1973 View Post
Sad for them, but not for you
Thanks!
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Old 15th November 2009, 01:07 PM   #6
eyoung is offline eyoung  United States
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Build it and they will come, somehow I think I've heard that before.
You certainly have my interest, keep it going.

Regards, Elwood
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Old 15th November 2009, 01:24 PM   #7
Zen Mod is offline Zen Mod  Serbia
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be brave .... and confident

about lack of attention to your thread -

greedy boyz like to have Papa's blessing for their usual hysteria

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Old 16th November 2009, 07:19 AM   #8
wensan is offline wensan  United States
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Quote:
Originally Posted by Zen Mod View Post
be brave .... and confident

about lack of attention to your thread -

greedy boyz like to have Papa's blessing for their usual hysteria

Maybe I am one of the greedy, too.
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Old 16th November 2009, 08:27 AM   #9
fff0 is offline fff0  Singapore
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Quote:
Originally Posted by Nelson Pass View Post
.....I am not
planning on making the circuit details public, so .......

Serious? Not even after hitting your quotas? hmm... guess I took it for granted but well... lets see how near we can get to the real J2...
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Old 16th November 2009, 09:09 AM   #10
Zen Mod is offline Zen Mod  Serbia
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Quote:
Originally Posted by wensan View Post
Maybe I am one of the greedy, too.
we are all ........
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