H2 Generator

[Algar_emi]

Hi Nelson. I want to build my own version of your H2 generator, since I was not at your Amp Camp I have all the parts in stock, including the J112. In the documentation you said they need to be matched for a pinch voltage of 2.0 to 2.5V for an IDSS of 30-40ma. Is it an error there since the J112 IDDS is about 5ma from the specs sheet, or I'm missing something?

Thanks
SB

 

[Algar_emi]

Hi. Finally saw that into the article it is explained, my error. Was reading it last night, too late I guess. Sorry for my stupid question
But I still think that the article should mention 3-4ma and not 30-40ma

 

[Nelson Pass]

That was not a J112 curve, just an illustration of the general idea.

J112 Idss is quite high, and would not ordinarily be used except that it
created the effect better than the lower current parts like J113.

 

[Algar_emi]

Thanks Nelson for the explaination. I'm still without clue on how to select the J112 that I have in stock for this little pcb. Can you give me kind of a procedure? I have a curve tracer, and a distorsion analyzer. Thanks
SB

 

[Nelson Pass]

I am using Vp of 2 - 3 volts and selecting parts from that population based
on the supply voltage in the circuit. The H2 can then be adjusted by the
supply voltage regulator. One regulator means matching requirement.

The DIY H2 coming up has two regulators, independently adjustable,
and the Fets are supplied with calibrated voltages.

 

[Algar_emi]

And it will be available at the diyaudio store? SB

 

[Nelson Pass]

Yes.

 

[myleftear]

Hi Mr Pass!
This „Yes“ was quite some time ago…
Is there still hope?