Aleph J-X Amp Project

[cka3o4nuk]

Hello dear comunity
can anybody point to the right shematic of Aleph J-X Amp?
cant find it on the thread

 

[derwhalfisch]

You need to refer to the manual for the Aleph-J. The amp is just two J's with their front ends replaced by a common circuit posted a few days ago by Peter Daniel. If you compare the schem of Aleph-J with the X frontend you'll be able to find the overlap.

Here is the Aleph-J.

 

[SCAIFF001]

populating the front end pcb

Hi everyone,

Is it just me or is populating the front end pcb is difficult to souder, the souder is not attaching itself to the pcb very well for some reason, is there anything I should do about this ?

Thank You

Ian

 

[qusp]

I had no problems, nothing different to any average PCB, the traces are not particularly thick, there is no ground plane to suck out the heat.

try some flux and perhaps higher heat. i dont know what else to recommend because if its not working normally there is something else at play other than the pcb.

are you using quad eutectic or lead free solder? what tip? although any standard tip should be fine

 

[h_a]

You definitely should do something about this as you risc cold solder joints otherwise. Besides the poor contact itself, it leads to crackling noises.

Use more heat! Hannes

 

[SCAIFF001]

clean souder iron point

Hi everyone,

Is it just me or is populating the front end pcb is difficult to souder, the souder is not attaching itself to the pcb very well for some reason, is there anything I should do about this ?

Thank You

Ian

I have been keeping the soulder iron point clean, or at least I thought it was, I have sanded the tip with sand paper and the iron works great now, I never knew that I had to do this sanding of the tip, and will redo all of my saulder iron connections when this problem surfaced.

Thank You

Ian

 

[SCAIFF001]

mounting P1

Hi,

I am at my last item of populating the pcb(s), mounting "P1". On the pcb there is a little circle with a line through it at one end of the white mounting rectangle with three holes in it. Dose the screw for the pentiometer mount at this end, or dose it not make any differance ?

Thank You

Ian

 

[Peter Daniel]

It doesn't make any difference.

 

[qusp]

sanding the tip will eventually lead to it failing quicker than if you just keep it properly and regularly clean with brass wool

 

[Peter Daniel]

Just to remind, that functional amplifier and some additional info were presented here: http://www.diyaudio.com/forums/pass-labs/145387-aleph-j-x-amp-project-27.html#post2012118

 

[john65b]

I have been keeping the soulder iron point clean, or at least I thought it was, I have sanded the tip with sand paper and the iron works great now, I never knew that I had to do this sanding of the tip, and will redo all of my saulder iron connections when this problem surfaced.

I put dull and dirty solder tips into a drill (like a drill bit) and spin the tip into a pinched fold of sandpaper to resharpen and clean solder tips. It's quick, and works great.

 

[SCAIFF001]

cleaning souldering iron tips

I put dull and dirty solder tips into a drill (like a drill bit) and spin the tip into a pinched fold of sandpaper to resharpen and clean solder tips. It's quick, and works great.

Thank You the drill works well, I wish I would of known this B4 I started populating the pcb(s).

Ian

 

[SCAIFF001]

assemblely of the populated pcb Front End

The front end pcb has four inputs on it, three for the XLR ballanced input, "+" & "-" & "grd", what is the fourth input "SG" ?

I will be using the XLR input, from the output of my computer sound card driveing optically a ballanced digital analoge converter from the following:

http://www.fetaudio.com/store, look into it it is an amazing DA converter, maybe the best DA converter money can buy, a perfect match for the Aleph J-X

Is there anything I have to do with my pcb(s) before installing them, any tests, or setting of the Pentiometer P1 ?

Thank You For Any Help

Ian

 

[oiphy]

Thank You the drill works well, I wish I would of known this B4 I started populating the pcb(s).

Ian

U shuold have a sponge moist,not wet. use it at all time when soldering. If using sandpaper on the tip you'll remove the iron on the tip thus ruining the tip.

regards

 

[qusp]

if you have a proper brass wool tip cleaner instead of a sponge you wouldnt need to do this. the wet sponge is bad for tips due to thermal shock cycling the tip each time. having the tip hot all the time is better than hot-cool-hot-cool and is the reason the surface becomes so oxidized

 

[derwhalfisch]

SCAIFF001, I think you should open a build thread of your own to get support.

 

[oiphy]

if you have a proper brass wool tip cleaner instead of a sponge you wouldnt need to do this. the wet sponge is bad for tips due to thermal shock cycling the tip each time. having the tip hot all the time is better than hot-cool-hot-cool and is the reason the surface becomes so oxidized

hence the moist not wet sponge..... when I took my solder sertificate (nasa approved) some years ago we learned tat the sponge was the best option. the heatcycling you refer to will happen anyhow when tip hits the soldering objekt...

 

[Peter Daniel]

The front end pcb has four inputs on it, three for the XLR ballanced input, "+" & "-" & "grd", what is the fourth input "SG" ?

When you check traces it shows that GND and SG are connected; SG means signal ground and is the same as GND.

I used two separate pads: one for input signal ground, the other to connect ground reference from the power supply.

I can't be much help in troubleshooting as I didn't built AJ-X yet, however the boards were tested and work fine if properly set up.

 

[qusp]

hence the moist not wet sponge..... when I took my solder sertificate (nasa approved) some years ago we learned tat the sponge was the best option. the heatcycling you refer to will happen anyhow when tip hits the soldering objekt...

well put it this way, using the hacko brass wool i'm still on the same standard tip that came with the iron i bought nearly 3 years ago and is the main tip along with a 2mm chisel I use for hours each day for work, as well as hours each day for hobby time. a wet/moist/whatever sponge will be more likely to give thermal shock, not just take the heat out of the tip like soldering does; ive never had to sand it, but hey use whatever works for you.

 

[SCAIFF001]

cleaning soulder iron tip

well put it this way, using the hacko brass wool i'm still on the same standard tip that came with the iron i bought nearly 3 years ago and is the main tip along with a 2mm chisel I use for hours each day for work, as well as hours each day for hobby time. a wet/moist/whatever sponge will be more likely to give thermal shock, not just take the heat out of the tip like soldering does; ive never had to sand it, but hey use whatever works for you.

I have been using the sponge along with the brass wool stuff for cleaning and only the drill seems to really work well for me.

Ian