Pearl 3 Burning Amp 2023

Good evening PEARL 3-builders,
today I started my boards the first time. It was a crazy day...
First, I adjusted the outputvoltages of my PSU to +-15 V DC - no problem.
Put two OPA2134 into the boards.
Switched on - no LED lighting - reversed. Repaired...
Switched on again - uuuh, LED on.
Some measurements (over the resistors):

voltages over pcb 1 pcb 2

R4 (10Ohm) 0,048V 0,048V
R5 0,048V 0,048V
R6 0,048V 0,048V
R7 0,048V 0,049V so, all JFets are running at 4.8 to 4.9 mA (ONSEMI 2SK2394)

R27 (220Ohm) 2,36V 2,37V circa 10 mA out of the J112- pretty high. Wayne suggests 2-5mA. I think I have to increasee R27
offset at output below 1mV 1mV was slightly fluctuating, but in both channels below 1mV!

R23 (22 Ohm) 0,34 V 0,338V
R24 (22 Ohm) 0,34 V 0,338V so, bias of the output BJTs is anywhere around 15,36 to 15,45 mA.

Enough for today. I am done.
Good night!
Dirk
This was the highest DC-offset at the output: -0,78 mV!



In total you get ~20mA IR1 -> UR1 is now 15V, Powersupply Rail 15V, what is going on with Q5 and Q8 ... 😳
 
Only for my new good friends "Zen Mod" and "spoiler", take note, it's a good Idea to know the voltage across R1 - better not exceed 5,7V.
e.g. 4 * 1,9 mA!
And that is why the kit you both trying to buy, uses 2SK209GR.

Please don't ask me about that figur, but be sure that i know it in the modus of deepsleep.

Bye,
HBt.
 
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Weren’t you the one who threatened me?

“If you like to battle, your are welcome - i am also an old Judoka.”

I asked you a simple and honest question - whether you had built a Pearl 3, as some here have already - so i could understand where your somewhat aggressive questioning of the design was coming from. Your response was to demand measurements from me of a device i do not have. So to me, you’ve earned my disdane the old-fashioned way.

I come here to learn from smart and generous people who are generally kind and supportive. Your pushy domination of this thread has ruined that for me.

Have a nice day.
 
You will learn about electronics and semiconductors, please ask! I am a very kind person, specific question are welcome.

"I come here to learn from smart and generous people who are generally kind and supportive. Your pushy domination of this thread has ruined that for me.
Have a nice day." [quote spoiler]


Thank you, have a nice day too,
HBt.

Psst.
I don't ruined everything and are not stupid (perhaps you should keep this it in mind)
 
Où est ma foutue perle 3 ?


1700623487313.png
 
void mea_culpa(void)
{
int ad_nauseum;

ad_nauseum = 1;

while ( ad_nauseum )
{
printf("%s/n",Most sincere apologies...");
printf("%s/n", "where is my Pearl 3?");
printf("%s/n", "Zut Alors... no need to get antsie, we're all friends around here! Hmm... Merde! I used french.... ");
}
}


+++

So, the Pearl 3 one box... will it interfere with a Pearl 2 PS? I'm running out of shelves.