F5 Turbo is posted

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This is too Cool !!!

After seeing some specs, I so want too build a set of these!!

It looks as if that they fill my requirements of at least 40Vpeak and into 1 ohm peaks as well for driving my DIY ESL's.
With a very simple circuit ,few parts and great specs to boot!

I already have a few large transformers in the 1000VA range that will work.
Just need to get the semi's and some very large capacitors and some sort of heatsink system,I have a liquid cooled type in mind maybe.

It will be awhile before I build a monster version but I will now start with the basic F5 though, as I was thinking about the AlephJ-X as well.

Thanks, Nelson Pass !!!

Jer :)
 
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For the JFETS, eBay seller "alweit" has well-matched pairs. Highly reccommended seller!

eBay - See alweit's JFETS here

:) Thanks.

Any idea if I can get the Fairchild output devices any more? I do have one set (unmatched) of the input pair but no output devices.

I assume with all the banter that any high-speed diode with a decent current reserve will do for the output stage.
 
How did you mount them to the heatsink? That TO-220 case looks weird. How many watts are they dissipating?

Same as i did for the TO247 or even the toshibas
Big piece of flat coper bar and 2 M4 (metric 4mm) bolts on super duper heat spreaders.

32V 1.3 A or 26 V 1.8A depending on the mood I got 100VA trafo with taps at 20 and 24 V
About 160 watts on each sink and recon they shuld be good for around 250 W whitout going over 50 C mark.

I am using Kerafoll 86/83 and with the bolts I can put loads more pressure on them than with litle M3 single srew.

Kerfoll show graph of thermal resistance against pressure on data sheet.

Loads more about it on MY F5 tread.
The grey wire in the first picture is a PT 100 probe I have used to monitor the TO220 case themperature
If you post there I will be happier to ansver any question you have witout boring soks off the rest of the population and hi jack this tread.
 

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