Babelfish XJ , or JX …….. or whatever (Aleph X servo for Greedy Boyz)

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CRC is what I would use and even then , never more than 0R1 for R

For the decoupled PSU in the other thread, the schematic posted by Jeff has resistor value at 0R33 (0.33 ohm). If I build these using standard Papa value 0R47 and do the math, each bank of 3 has parallel resistance of 0R16 ... but these banks are in parallel to each other from the first cap bank so effective resistance is 0R08 (0.08 ohm).

Is this ok and even if it's wrong math, am I worrying about nothing?

Link to schematic:

Alternate First Watt Power Supply Schematic
 
Official Court Jester
Joined 2003
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say that my fave format of caps for rails as in this case is 33mF/25V

so , as minimum , I should go with 2 of these , then 0R1 then 2 of these ........ more precisely 66mF-0R1-66mF

of course , increasing value of C cells is good , so 99mF or even 132mF ...... why not

0R1 - for nice and cozy sleep - use 25W metal goldies (cheap on fleabay,popping everywhere) , screwed to bottom plate

when using snap-in caps (especially plenty of them in C bank) , easiest solution for pcb is heavy copper raw pcb , use back horn of exacto knife along metal ruler to make cuts/channels for forming pcb fields

then 2mm drill for caps pins , 3.2mm drill for screw holes in corners , isolate corners from rest of pcb

then some thinking with (hopefully) smart outcome to position take-in and take-out wires and that's it

if you need nudgenudge regarding that , just say

your pcb are at shelf (arrived) , mosfets too .... now I need to find/organize lazy afternoon** to do some (enjoyable) matching and to remember these days to order some flat cables and IDC connectors

** lock the door , turn off cell and land line , brew some coffee .....

edit: album for tonight : YouTube
 
Official Court Jester
Joined 2003
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with 18Vac secondaries (preferably two independent ones per xformer , so going with two bridges route) , you'll end up with something as 22V5dc rails

if you're going for custom xformers , you can use few volts lower secondaries , no biggie

you need volts to keep mosfet capacitances polite , but you don't need so much volts for power ..... damn thing is already monster , at least for my criteria
 
Official Court Jester
Joined 2003
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when I was in States , I bought one bag of 500pcs of J309 and one bag of 500pcs of J271

J271 is good enough for Aleph -like stages , when biased with CCS - no problem with highish Idss (comparing to Toshibas)

I believe nowadays you can find both of them in SMD case

though , if you're thinking and planning as regular Greedy Boy , just one step ahead .... just buy Toshibas from few reliable sources , or LSJ from Store

me - I'm hoarder , when speaking of parts