F6 Amplifier

[dimkasta]

Originally Posted by Papa

I'm only going to make 10, and there is no intention to sell them, so it's
strictly DIY.

Not that we greedy boys do not appreciate the selfless contribution.

[Skorpio]

Originally Posted by Nelson Pass

Now that the cat's out of the bag via BAF, here is the official F6 schematic.

There are several versions, but I am building 10 channels of this for in-house
use. There is a version without the input buffer, and a couple of versions
showing degeneration on the input devices and degeneration on the outputs,
which I have not chosen to use.

Very exciting design

Is the feedback compensating for the transformer distortion? I mean like this:
http://www.lundahl.se/pdfovrigt/feedbck.pdf

[Sandor]

Will the F6 work with SIT devices?
And are those SIT devices currently available?

[CeeVee]

Originally Posted by Sandor

Will the F6 work with SIT devices?
And are those SIT devices currently available?

have u done any research ?...you should before asking.

[Sandor]

Originally Posted by CeeVee

have u done any research ?...you should before asking.

I've just hoped to get news from Nelson about SITs.

Neslon, is there any chance that we will see a SIT-F6? What about the availability of SITs?

[Nelson Pass]

You can build this circuit with just about anything, and that is the point of
such a topology. The Jfets I used are nice parts, but not the central thing.

The central thing to me was a nice passive way of isolating and splitting the
drive for the devices while at the same time implementing feedback, all done
passively by the transformer.

Sits will work fine, as will ordinary Mosfets.

[Rush]

Originally Posted by Nelson Pass

Sits will work fine, as will ordinary Mosfets.

Do the output devised need to be matched? If so how close?

Rush

[Tea-Bag]

A SIT or depletion mode device I would think would need some alterations to run negative voltage to the gate.

[buzzforb]

Rush has a very good idea, IMO. Dont tell, Rush, until i can get some ordered.

[dantwomey]

Originally Posted by buzzforb

Rush has a very good idea, IMO. Dont tell, Rush, until i can get some ordered.

Come on now I can't keep up! F5, L'AMP, F6! I should just buy shares in Plitron/Digikey.

P.S. Many thanks to Nelson for his generous support of the DIY community!