Aleph J Schematic

[Zen Mod]

 

[schultzsch]

you know...it serves a couple, but I`ll wait untill I finish the mechanical works too

 

[schultzsch]

In theory they are finished but in practice...I really don`t know


reminded... there are missing some 6.8nf caps on trafos secondary windings

 

[Zen Mod]

much better ( if you're having same opening on bottom)

 

[schultzsch]

the bottom has same lateral holes as the top plus some holes in the middle(same holes you can find on the board that holds the caps as you can see in the 3rd picture)
I was thinking to use some 5mm distantials between bottom and fixing system.
what do you say? will it do the work?

 

[Zen Mod]

calc how big area you have now , opened at bottom and say percentage , comparing to opening at top

 

[schultzsch]

top is almost 5 times more opened than the bottom

 

[Zen Mod]

then put that spacer thingies on screws for bottom

airflow is a must

 

[pmchoong]

Hi, I am using 2sj109 on Peter Daniel's board. Do I need to solder pin no 4 or leave it?

 

[Zen Mod]

leave it

 

[pmchoong]

Thanks, zen.

 

[pmchoong]

But what is the use of the hole there for? It's not use with matching j74 either. It's just kind of confusing.

 

[Zen Mod]

2SJ109 is having that middle pin , so it's not confusing

my Jaccolina is knowing what's purpose of that pin , I'm dumb

 

[tinitus]

top is almost 5 times more opened than the bottom

better than the other way round
that perforated plate looks very open

 

[pmchoong]

aleph J distortion

Hi All,
I have a problem with my mono Aleph J, which is very similar to Anilva's. Please see the attached measurement (in Red)of my Aleph J. The only thing I am not sure about is the Q4's measurement.....which seems out of place. The sound from the Aleph J's will distort when the volume is increase....just around 1/4 turn of te volume knob only. The other things that I have noticed is the heat sink is not heating up well and the rail's LED (i have a LED in place at the power supply rail since Peter's board doesn't have one) stays on at least 15 seconds after I have switch off the power supply. Thank you in advance.

 

[Zen Mod]

judging by voltages across source rsistors , you're having decent Iq ( around 2A5) which gives around 135W of dissipation with 27V rails

however , taking in account what you wrote for PSU leds , something is wrong - you can't have 130W of heat and cold sinks , same as slow dying LEDs with 2A5 Iq

pictures ?

 

[pmchoong]

PSU board

This picture shows the PSU and the Main board on top

 

[pmchoong]

PSU board

The Fets are mounted on the heatsink with the along with the gate resistor.

 

[pmchoong]

Are the pictures clear enough or should I retake them?

 

[pmchoong]

This picture shows the bridges...25A at 400V