MPP

[Joachim Gerhard]

You are not blind. Again this is a joke that is hard to translate. I even wanted to express that you had some luck, Ricardo. The NPNs from Reichelt that i got are not usable in this circuit. They could be used in the mirror but i found no PNP matches.

 

[hesener]

a little teaser.....

Here a screenshot of the ground plane arrangement.

on the left side is the (input) star ground connection
lower righthand corner is where the power input is connected
GND1 and GND2 are the ground connections of the input elcaps and cascode voltage filtering (including the zener string etc)
GND3 is the ground connection of the RIAA filtering components
GND4 is the ground connection of the positive shunt regulator
GND5 is the ground connection of the negative shunt regulator

GND1,2,3 are connected with wires to the star ground, whereas GND4,5 are connected through their ground planes

Honestly, I've tried my best. But I am open for any suggestions or improvements, just let me know!

 

[Benedetto]

@Ricardo:
~até uma galinha cega encontra um grão, uma vez~
or so.
G8gle said.

 

[Joachim Gerhard]

I like the ground connection by wire. I am not an expert on PCB design so i can not judge how good that layout is. I simply trust you and when there are still small bugs we will again make a group effort to erode those.

 

[Holger Barske]

@Hesener:
Thanks you very much for your efforts. Mind posting a bigger version of that ground layer pic?
And, even more important: You might want to avoid the jpg format for graphics. Jpg always gives blurred results on those. Try an indexed color format like gif or png.

 

[hesener]

@Hesener:
Thanks you very much for your efforts. Mind posting a bigger version of that ground layer pic?
And, even more important: You might want to avoid the jpg format for graphics. Jpg always gives blurred results on those. Try an indexed color format like gif or png.

ooops, thanks for this tip!! the png file (although hires) is only 40kb.......

 

[Joachim Gerhard]

That looks very good. Good tip, Holger.

 

[Holger Barske]

As "star" as it can be. Looks good to me.

 

[RCruz]

Looks very good and I like the idea of connecting GND by wire... One question.... Why the star gnd at the input ?

I am using star gnd at the output (on the output RCA´s) with great hum reduction results.

PS JG: Luck is an atitude.

I consider myself lucky and I am glad you do not think I am blind...
I was unhappy because I lost the meaning during translation and I thought you meant: "Deus dá nozes a quem não tem dentes" "God gives nuts to those who have no teeth"

Now I know you did not mean that

 

[Joachim Gerhard]

That i understand. It is the most sensitive place in the circuit.

 

[Joachim Gerhard]

One more bad joke : the most stupid farmers have the biggest potatoes

 

[Joachim Gerhard]

You can not have everything i suppose.

 

[Benedetto]

"God gives nuts to those who have no teeth"
Real nasty one.

 

[Joachim Gerhard]

You can hit them with a hammer...

 

[RCruz]

It is true..... I usually see very old peolple driving Porches and Ferraris. Why is that if they do not have the speedy reactions of a youngster to be able to use those machines at full blast ?

 

[Joachim Gerhard]

Compensation maybe for something they lost. Also older people have usually more money then young ones when i trust the statistics.

 

[RCruz]

One more bad joke : the most stupid farmers have the biggest potatoes

No that is really awfull

Imagine a stupid blind chicken full of goodies. It might be dangerous.

Anyway, I got my trannies from Frans as well as Salas and ours are ok... Nothing to do with luck I guess.

 

[RCruz]

Compensation maybe for something they lost. Also older people have usually more money then young ones when i trust the statistics.

Well it is a pitty that those machines are so expensive. One needs to work a whole life to be able to reach them. "Falo extensions?"

 

[Salas]

When we go to print some PCB? I want many many BJTs MPP phono JG guided team thing collector's item limited edition after reading this thread for long. Plus it has shunts with leds and 9240s which I am kinda fond of...for some reason.

 

[Joachim Gerhard]

The transistors from Frans i got where good too so we have a reliable source. It is not a big deal anyway. I just feel responsible that this project does not fail and everything goes as smooth as possible. It will be exiting when the first ones play.