DIY F2 clone

[Nelson Pass]

BTW, this question has been asked before and will inevitably
be asked here - "Why the .33 ohm resistors, inductor, and
10 uF cap?"

The .33 ohm resistors are inductive wirewounds, and the
inductor in the schematic represents that. When I laid the
board out, I anticipated a large capacitor in the decoupling,
but it didn't work out best that way, and I ended up trimming
the values against the following square wave at 10 KHz:

[Netlist]

I'm I right if I recognise a ZenV2 current source? I presume a variant with two IRFP240's would work as well?

/Hugo

[Nelson Pass]

Originally posted by Netlist
I'm I right if I recognise a ZenV2 current source? I presume a variant with two IRFP240's would work as well?

I imagine so, although I did not try it. Note the 15,000 uF
cap in the current source charging circuit. An amplifier of this
low wattage will be paired with delicate drivers, and
avoiding turn-on thump is a priority.

[lineup]

Originally posted by Nelson Pass
Here we go

Thanks Nelson Pass
Many girls and boys will be very happy
... like getting an early X-mas gift

I attach the image of your schematic
for those who want to take a quick look,
without download of original PDF

lineup
------------------------------------------------------------------------
this image, as all 'pass-materials', is now put with all the rest of my collection in folder C:/My Documents/Nelson Pass

I have separate folders, for like 60-70 other audio persons and diyaudio members, too.
Including one folder for 'lineup circuits and stuff', I have manage to find in this forum + world wide web

Attachment:
First-watt-f2-sch.png

[Zen Mod]

Originally posted by Netlist
..........................

Is there a particular reason to do the series/parallel resistor bank instead of one or two resistors?

/Hugo

certainly like always............Papa have it muuuuucho in stock........

not to mention few possible technicall reasons...

[Netlist]

So, are you saying that a current source with P-channel devices is more immune to those thumps than an N-channel version? Or that a 15.000µF cap can not be used in a N-channel version? No, can’t be… although …is there a relation?

/Hugo

[Nelson Pass]

A different method for slow charge would be required to
bring up the N channel current source. No doubt it could
be done easily, and no doubt one of you will come up with
the appropriate variation.

[steenoe]

Congrats guys

Steen

[Babowana]

What is the function of R1 (1M)?
Thanks, Nelson.

[Zen Mod]

Originally posted by Babowana
What is the function of R1 (1M)?
Thanks, Nelson.

protection;
in case that preceding stage doesn't have same purpose resistor after coupling cap.
Papa must put this there,his amp is (sort of) commercial.
you are not obliged to do the same