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Old 3rd February 2012, 04:55 PM   #591
ra7 is offline ra7  United States
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Ok... so, if you change the source resistor, the amount of current flowing through it will change, correct? It just happens that a 1 ohm resistor is about where we want to be in terms of current draw.
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Old 3rd February 2012, 04:57 PM   #592
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Quote:
Originally Posted by ra7 View Post
...It just happens that a 1 ohm resistor is about where we want to be in terms of current draw.
that's too much of coincidence , if you ask me

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Old 3rd February 2012, 05:11 PM   #593
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juanitox @the R-core is hot ? your suggention is for 2x500VA or the 2x300VA is sufficient ?

Humm I have only one 500VA 30Vac...
Tnx
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Old 3rd February 2012, 05:11 PM   #594
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When I was experimenting with ZV9, with a choke load, there was this other interesting enthusiast we havent seen much of lately. Maybe some of you have not seen before "The Donut". I'm not sure what to call it? If you know Magura, you know:-) If this is new to you???
ZM!, what is it I want to send them to. A monster differential choke loaded donut borrowing from ZV6, 7 & 9?
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Old 3rd February 2012, 05:11 PM   #595
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hahaha... yes. Thanks ZM!
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Old 3rd February 2012, 05:28 PM   #596
Zen Mod is offline Zen Mod  Serbia
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........
ermmm ... and what is a question ( pardone moi , non native English writer ) ?

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..... A monster differential choke loaded donut borrowing from ZV6, 7 & 9?
nope ...... Donut is completely original , never seen before , best thing after bread

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Old 3rd February 2012, 05:30 PM   #597
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juanitox @the R-core is hot ? your suggention is for 2x500VA or the 2x300VA is sufficient ?

Humm I have only one 500VA 30Vac...
Tnx
no the 300VA R-core stay cold , no problem on that side
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Old 3rd February 2012, 05:39 PM   #598
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..... Donut is completely original , never seen before , best thing after bread
O.K. but it's not something like a Qspeed Cascoded diff-amp with choke load( combination ZenV7 and ZenV9?)
But it is choke loaded. With Magura chokes!
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Old 3rd February 2012, 05:42 PM   #599
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Q. What controls the amount of current through the CCS? Is it the bias voltage on the SIT or the Vgs of the IXTH? Or both?
It does feel a bit "chicken or the egg" doesn't it?

As ZM points out, the MOSFET is self-biased, and we're using the adjustable voltage reference to balance the currents and put the SIT drain where it needs to be. You could use a slightly smaller source resistor and run with higher current, but I found that wasn't really necessary as it didn't have a big impact on performance. Also, the bigger source resistance helps stabilize the CCS a bit. I included a spot for RTRIM, a trimming resistor, in the drawing in case you want to really fine tune things.
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Old 3rd February 2012, 05:55 PM   #600
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This is not an issue with a big, heavy ga. air-core.
Iron is another matter, though.
Be sure to grab that pdf when you get home.
Well bud, so far I guess I know why you said that. I can all but guess the vailues on the Iyxs CCs with what, a TL or other bias idea in mu folower???
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