Last edited:
Hey Zen Mod, I'm using Toshiba 2SK1530/2SJ201 as well. Is this bias tweak to get the Toshiba's to a more optimal operating point and to coax a bit more current drive, since these are lower transconductance parts than Fairchild and IRF parts?
Thinking about putting 1R3 parallel with 0R47 and 10R parallel with 221R so as to compare the two Iq's.....hmm
Cinco
I would PM buzz....I suppose your heatsinks are warming up and you are getting proper measurement across source resistors? Or no?
Russellc
When Justin put his boards up for sale he mentioned an error which requires wrapping the source resistor around the soldered leg of the MOSFET. Did you do that?
http://www.diyaudio.com/forums/swap-meet/282086-pass-m2-clone.html#post4507731
Source resistors are warmed up and sitting at 0.63vdc
C2 measures 333. mvdc
Both C2 capacitors are connected so + is to transformer, same as in schematic.
22V + and - testing to board ground.
C3 is 10V
Grinberg,
Yes I did fangdangle the one board to match the schematic. basically swap the grid and source on the one IRFP FET
C2 measures 333. mvdc
Both C2 capacitors are connected so + is to transformer, same as in schematic.
22V + and - testing to board ground.
C3 is 10V
Grinberg,
Yes I did fangdangle the one board to match the schematic. basically swap the grid and source on the one IRFP FET
Last edited:
Looks like both transformers are broken🙁
pin1 to ground = no connection. It should be 230r or so.
Thanks for everyones help. 🙂
pin1 to ground = no connection. It should be 230r or so.
Thanks for everyones help. 🙂
The transformer's wiring on Buzzforb's PCBs does not match the published schematic. He swapped pins 1 and 3, 7 and 5.
If you are wondering how do I know that, the answer is: I have an unused pair of his boards.
Attachments
Last edited:
so - is it pcb , or damaged xformers ?
I would triple check xformers , carefully referring datasheet
I would triple check xformers , carefully referring datasheet
stop confusing us 
check xformers per datasheet
desolder them from pcb (carefully!!) if needed
or wait for confirmation from anyone who already made it with same pcbs
check xformers per datasheet
desolder them from pcb (carefully!!) if needed
or wait for confirmation from anyone who already made it with same pcbs
I was confused first. 🙂
after soldering little hair strand on the output winding of transformers magical sound is now playing.
It might be a good idea to drop a little crazy glue on these little wires where they attach to the post to keep them stable.
after soldering little hair strand on the output winding of transformers magical sound is now playing.
It might be a good idea to drop a little crazy glue on these little wires where they attach to the post to keep them stable.
....after soldering little hair strand on the output winding of transformers magical sound is now playing.
Congratulations Damuffin
Hi Russell,
The alephj is very nice, I preferred it over the F5, but I also preferred the F6 over the Aleph J on my system. The bass is very good on the F6. I'm using a tube pre (Aikido) with it, a very nice combo. I tried several SS Preamps but the Aikido is hard to beat.
Paul
The alephj is very nice, I preferred it over the F5, but I also preferred the F6 over the Aleph J on my system. The bass is very good on the F6. I'm using a tube pre (Aikido) with it, a very nice combo. I tried several SS Preamps but the Aikido is hard to beat.
Paul