Does anyone think same like me ?
Using irf9610 for cheapest diff input and combine to J2 Mu-Stage output but use m, sfet as current source, posible ?
Using irf9610 for cheapest diff input and combine to J2 Mu-Stage output but use m, sfet as current source, posible ?
Could someone calculate olg when used mosfet instead of jfets input ?
I need to know IDSS for this modded.
I need to know IDSS for this modded.
FE...Ahhh I just know.
Now I have 2+2 Pcs of R100A and R125, Do they different when I use as SE with Mosfet currenr source ?
Sorry for my newbie.
Now I have 2+2 Pcs of R100A and R125, Do they different when I use as SE with Mosfet currenr source ?
Sorry for my newbie.
As far as I know R100 has thermal run away, then can I control vgs as I've done with Aleph portion mosfet ccs ?
As I mention R100 is different from IRFP240 which used in Aleph 3, 30 then how do I control vgs of R100, R125 ?
Only trim pot ?
Only trim pot ?
This's what my idea.
Combination of Aleph and Jfet Mu Stage, M-MU-J or M.u.J
Combination of Aleph and Jfet Mu Stage, M-MU-J or M.u.J
An externally hosted image should be here but it was not working when we last tested it.
feel free to experiment
you have finished recipe for Mu with IRFP - in ACA schematic
besides that - if you have values and sch of J2 , be aware of fact that Pa didn't published that schematic
you have finished recipe for Mu with IRFP - in ACA schematic
besides that - if you have values and sch of J2 , be aware of fact that Pa didn't published that schematic
An externally hosted image should be here but it was not working when we last tested it.
I found something wrong with my trimpot. It should be liwer than 500 Ohms because R100/125 need vgs 1.2V across thus trimpot and IRF9610 need bias current 12mA/ea then trimpot must be around 100-200 Ohms for 1.2V/100Ohms=12mA
yes that sounds about right - although i think you would be best placed keeping the drain resistor load as a fixed value (say 200 ohms or so) and then adjusting the CCS set resistor R11 in your schematic. You 'loose' less gain by adjusting current for a given Vgs vs adjusting the drain resistor and keeping the current constant.
Also the macmillan resistors are neat but maybe for test and development purposes you can just use a low value trimpot between the source of the LTP fets for offset adj purposes (which is what those resistors are meant to achieve)
As regards the choice of the input mosfet, there are other devices you can try nowadays - some alas not easy to find (SJ313) and others still available (IRF9Z24). You'll find that these devices have their own 'sweet spot' (combination of drain resistor and bias current) and so may be better suited for the job of driving the jfet op devices. Only way to find out which is best is (imho) through plenty of experimentation.
Good luck mate!
Also the macmillan resistors are neat but maybe for test and development purposes you can just use a low value trimpot between the source of the LTP fets for offset adj purposes (which is what those resistors are meant to achieve)
As regards the choice of the input mosfet, there are other devices you can try nowadays - some alas not easy to find (SJ313) and others still available (IRF9Z24). You'll find that these devices have their own 'sweet spot' (combination of drain resistor and bias current) and so may be better suited for the job of driving the jfet op devices. Only way to find out which is best is (imho) through plenty of experimentation.
Good luck mate!
I'm not seeing McMilan resistor there
as I recollect , those are sort of support for Tail node of LTP, acting as Terra Firma , so demanding two opposite originating nodes .... usually found as balanced outputs
as I recollect , those are sort of support for Tail node of LTP, acting as Terra Firma , so demanding two opposite originating nodes .... usually found as balanced outputs
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