Thanks, sorry If I sound a bit impatient at times im just eager, do appreciate the help!
yes if i connected +PGND and -PGND it would be good however what I find hard to get my head round is that my transformer only has 3 wires on secondary so i presume i cannot actually make that previous circuit and will have to use Single Graetz as only option
or
this circuit which with 2x24v would be too high voltage anyway, this is preferred to me by far but a shame as the output voltage would be too high
An externally hosted image should be here but it was not working when we last tested it.
Why would this give you 42Volts? The transformer used above is 2 x 25 Volt and gives an output of 35 volt ( without load ). So with load ( I calculate factor 1,305 always) and 2 x 24 Volt it will be around 31,5 Volt....
Yes, it gave me the voltage I needed thanks 32v x 2 so I wired up this new point to point PSU with bridge rectifier and bang...
no the amp didn't blow up but I still had a ground loop! exiting! lol even when the right channel was almost total disconnected apart from the earth and RCA input.
So yeah same problem when both RCA are connected Hum, so here we go take 3 Time to mess with the grounding further! my insanity levels are being pushed perhaps that's a good thing ?
PS: its not as stressful if the project your making is for yourself! this ones for a friend and long overdue, £800 in parts, nice price that
no the amp didn't blow up but I still had a ground loop! exiting! lol even when the right channel was almost total disconnected apart from the earth and RCA input.
So yeah same problem when both RCA are connected Hum, so here we go take 3 Time to mess with the grounding further! my insanity levels are being pushed perhaps that's a good thing ?
PS: its not as stressful if the project your making is for yourself! this ones for a friend and long overdue, £800 in parts, nice price that
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67 DEG heatsink
75 DEG washer on Mosfet
Bias 60mv or 0.06v across R1, target is 0.3v ! how the hell can i reach that lol
Any comments on this ? am i reading something wrong and have biased it way too high ?
That temperature is freaky at such low bias. by the time i make 0.3V across R1 this amp is going to be fried!
The heatsinks are massive!
75 DEG washer on Mosfet
Bias 60mv or 0.06v across R1, target is 0.3v ! how the hell can i reach that lol
Any comments on this ? am i reading something wrong and have biased it way too high ?
That temperature is freaky at such low bias. by the time i make 0.3V across R1 this amp is going to be fried!
The heatsinks are massive!
You can, but that transformer will run hotter and not cost that much cheaper than 2 transformers with the same combined VA rating.
yes. there is not much more cost. and it can do wonders
from what i've seen. the noise issues are less with dual bridges. at least with single transformer.
Don't use those precious JFETs in the cascode transistor position, rather use a normal BJT and save those JFETs for other Pass goodies. Use those Toshiba BJTs that Papa mentions in his article. I think it was the 2SA1837/2SC4793 complimentary pair.
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Yes It will not be used. Cascode transistors are marked as Q5/Q6, I will used 2SA1837/2SC4793 for these. Im referring with Q1,Q2,Q3,Q4 which is a parallel jfet slot. BTW im referring with the store PCB.
Hi Buzz,
Is this referring to my query?
Does it mean im good at 7.3ma parallel pair or single pair?
Lets say 45V rail voltage.
Cheers.
Hi Walter,
This is great information. Have you change the value of R5/R6(V3 Schematic)
to 2.2K or you stay at 1K. Just making sure for me to avoid rework.
BTW, what is your rail voltage for your V3?
Cheers.