Slewmaster - CFA vs. VFA "Rumble"

Terry, I've got an idea, hopefully a good one 😛

On the 10-th (in the evening) and on the 17-th (in the morning) I will drive from LA to Las Vegas (10-th) and back to LA (17-th).
I will definitely use 15-th freeway, going just through Victorville. Great opportunity to stop by and shake your hand 🙂
Practically, on the way back (17-th) - would be better, I think. Of course - if fine with you. Let's chat via e-mail.

Cheers,
Valery
 
Terry, I've got an idea, hopefully a good one 😛

On the 10-th (in the evening) and on the 17-th (in the morning) I will drive from LA to Las Vegas (10-th) and back to LA (17-th).
I will definitely use 15-th freeway, going just through Victorville. Great opportunity to stop by and shake your hand 🙂
Practically, on the way back (17-th) - would be better, I think. Of course - if fine with you. Let's chat via e-mail.

Cheers,
Valery

Hey Valery, that would be way cool! Looking forward to it. Let's keep in touch and hopefully we can make that happen.

Blessings, Terry
 
Sure (below). To go two layer , the ground star is the cause for most
of the jumpers. Run this on top (2 layer) and PCB will be jumper-less.
Diamond rail connections also make for jumpers.

Best to keep the "A and B" connections for the diamond. The twin red led
cascode co-efficient is opposed by the diamond co-efficient.
It should be close with either A/B , but A will increase the diamond.
If "B" turns out the closest , lower Vceo diamond pairs will be usable (>24V).

OS

ΟS many THANKS
Soon I will show you my results, I trust the work that my friend θυμιος makes 100 %.
Regards Nikos
 
Is there going to be any changes to the final schematic for Kypton-ND or is it safe to do a layout for it?

Yes , if you leave "A/B" , I can not foresee any improvement or "tweak"
that the present layout leaves unaccounted. PS - A/B can be bridgeable
SMD pads like JK did for the "wolverine" options.

This is the last of the CFA's , unless I can find another unique topology.
The kypton C is a good amp , too. Nearly the same as this one .
It is a test of whether the lazy cat "VSSA" or Bonsai's "NX" have the best
performance -SQ. I have a feeling it is the latter (no stinking caps).

On to the next one - it is !
OS
 
Is there going to be any changes to the final schematic for Kypton-ND or is it safe to do a layout for it?
An smd version!
You know the way, i'm sure you can🙂
1)Amplifier as built ,if this is useful
2)Rise time
3)offset without servo(inp.shorted)
 

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An smd version!
You know the way, i'm sure you can🙂
1)Amplifier as built ,if this is useful
2)Rise time
3)offset without servo(inp.shorted)

Did you try yours with Q1 and Q2 at full rail voltage? I'm curious if there was any difference. I've found some nice SMD complementary pairs in one package that is nice to lay out but they are only 60V devices. They should work well on the 12V rails.
 
That's what option A and B are. I didn't look at OS's layout. Did he have that option on the board?

Yes , they are there ! That's what I've been trying to tell y'all.
"A" gives higher slew rate !
A/B difference is also the level of diamond thermal co-efficient.
For the through-hole , leave the option - also , a universal CBE/ECB
would be nice for Q1-2 (any diamond pair option).

PS-Thimios used B and Still4given uses A - both work (but what are the
thermals - one should end up perfect ?)
OS
 
I felt Q1/Q2 and they run pretty warm but then, I didn't use the little heatsink like Thimios did. I used KSA992/C1845. I suppose I should have matched them better but it runs fine. I didn't use a socket on this one so I couldn't try it without the servo. I played it for about 4 hours and the sink on the VAS barely gets warm so it is probably not needed. I'd like to build another one and try the B option with low voltage devices but I'll probably wait until Jeff finishes his layout and have some boards made.
 
Change R4 and R7 to 8.2K. Also change R18/19 to 560R.

Then Q1-4 will be at 1.4ma , instead of 2.3ma. Ivas will = 5.4ma.

The IPS should perform identical , but run much cooler at your
higher rails.

With thimios's 50V rails , even 2.3ma would stay cool with no heatsink.

edit - I am running "kypton C" input pair at just 1.2ma @ 73V rails - ice cold.

OS
 
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