F6 Amplifier

I would like to start an F6 project, and want to obtain PC boards and semiconductors as a first step. Can anyone recommend a good version and source for these? I have spent some time looking here and googling, and I just to make sure the parts are not already collector's items (like some of the F5 parts appear to be).
 
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Ask him how big the stash is...:)

But what I can say that his matching quality is superb, not only Vgs, but shape of the transfer curve, means transconductance etc. included, he simply has a very expensive curve tracer.

Look at the experience of dsdjoy here some pages back..
How long he can offer this quality of matching, I do not know.....:confused:
 
As astutely pointed out by Generg, it is both (i.e., stash + professionally equipped lab). You have to start with a big pile of parts to sort it down into small piles of matched parts. But I've been learning on the job. The real thanks goes to our German friends who have been rather exacting in their requests and generous with the results (aka dsdjoy, post #5149). ;)

For those that are flexible on the part number, the size of the inventory needed to do the job of close matching of both the dc operating point (Vgs) and the ac reproduction (transconductance approximately, but really the shape of the transfer curve to be exact) is still available. Email michael.mazzola@impowersystems.com to learn more.

Ask him how big the stash is...:)

But what I can say that his matching quality is superb, not only Vgs, but shape of the transfer curve, means transconductance etc. included, he simply has a very expensive curve tracer.

Look at the experience of dsdjoy here some pages back..
How long he can offer this quality of matching, I do not know.....:confused:
 
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Joined 2009
Paid Member
Hi F6 builders....! :D

Two friends of mine adjusted the 1.2 V at the SemiSouth from source to gate and...the Semisouth got not warm, means no bias through them.
I encouraged them to turn the bias pot more and to measure the real current through an ampere meter.
The Vgs threshold of the SS is so different that the 1.2V are not always the right value.
I have seen in the curve tracer SS starting at 0.7V (out of spec) and other around 1.8V

So measure the real current, of course you can insert a small resistor in the neg or pos rail like Nelson in the 6moon version. 0R1 is a possible value and turn the pot unti you see 150mV over it for the 1.5A wanted.

Good luck and do not give up turning!:D:D
 
my F6 use 2SK1058
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