Complete Novice Needs Help

[KatieandDad]

Say, I have noticed differences in part numbers between the original Aleph 30schematic and the part numbers as used in Brian's boards. I have searched the chip amp site, but only find BOM lists.....is there a schematic somewhere that shows brian's version? I have the original schematic, just not the version for Brian's boards. I am easy enough to confuse already...

Thanks,

Russellc

Have a look at KK-PCB.COM. If its not right it will give you a few clues.

 

[richluvsound]

Yes, bleeder as seen in F5 power supply. 2K2 / 3W parallel each 1st capacitor (V+, V-) after rectifiers. You can also use thermistor ( CL-60 ) in series with mains, to get the thump damped.

Best,

nAr

Thanks Nar,

I have CL60 on secondaries before PSU ? Its not a huge thump ,but I would like to get rid of it

Rich

 

[richluvsound]

I'm sure Bill no doubt had it.....

Russellc

Hi Russell,

I have the BOM I used, it does have a couple of mistakes though .

 

[nar]

Thanks Nar,

I have CL60 on secondaries before PSU ? Its not a huge thump ,but I would like to get rid of it

Rich

You can try add one on mains side, series with one polarity of 230V.
To get rid of it completely, use a temporized relay to switch speakers on delayed after the thump. This can be coupled to a DC offset detection to protect speaker against a fault on the output.

Best,

nAr

 

[Russellc]

Have a look at KK-PCB.COM. If its not right it will give you a few clues.

Have that, problem is I have the boards from brian....that's why I would like his schematic. In the midst of building, its just another way to make a possible mistake. I like to ID part, find it on schematic, check proper orientation, check against bom, double check part, then solder. Its just a point of confusion when the schematic numbers dont match the BOM....I guess I can draw one out, but then there is another possiblity of mistake! I know I have seen a schematic for Brian's boards, lost a lot of old bookmarks when old computer croaked! I have the service manual, with Pass schematic, the Algar schematic, (Thanks Zen Mod) just not the one for brian's boards, whose BOM part numbers dont match the aforementioned....



Russellc

 

[AudioSan]

Have a look at KK-PCB.COM. If its not right it will give you a few clues.

KK-PCB do not have aleph 30. only aleph3.

 

[jimbo51]

Is this any use? Looking at the properties it was created by Brian.

 

[AudioSan]

that may be it

 

[richluvsound]

Yep, thats the one I used in the end . I think I went through 4 sets of Brian's boards (it was my first ever build ) ,but now up and running perfectly , apart from the click when I turn it off ....

Beautiful tube like sound

Good luck Russell .

 

[richluvsound]

You can try add one on mains side, series with one polarity of 230V.
To get rid of it completely, use a temporized relay to switch speakers on delayed after the thump. This can be coupled to a DC offset detection to protect speaker against a fault on the output.

Best,

nAr

You mean on the live ? .... Sorry for being dense !

 

[Russellc]

Is this any use? Looking at the properties it was created by Brian.

Yes, I do believe it is! Thanks you guys!

Russellc

 

[nar]

You mean on the live ? .... Sorry for being dense !

Yes, live, or mains. I believe it's the same thing with different names

Best,

nAr

 

[richluvsound]

Finally got back to this !

Hi Gents,



finally got back this as the warm weather is here and I don't need the extra heat of the XA 160's

Got it all running of sorts . One channel running perfectly , heat ,sound !
The other channel ,no heat and distorted sound . Trying to trace the fault .
I'm hoping someone can help me trace the issue step by step ?

I have been struggling for a few hours as they are boards from ebay and probably not sanctioned copies so I've not wanted to incure the wrath I can't get on with Brian's boards ..... too small for me .

I have 30 VDC rails from the PSU .

This is the Schematic I got with the boards :

 

[Zen Mod]

piccies pls

then little flack for being cheap and blind bstrd

then we can help

 

[richluvsound]

Cheers Zen,


they weren't cheap ..... ! I know it has to be something that switches . I have replaced one ZTX ,but thought I'd get help before I got too carried away .
Here's a couple of photo's .

 

[richluvsound]

Other end !

The other half !

 

[Zen Mod]

triple check values of all resistors , orientation of little bjt bstrds ( big ones even if you intend , you can't mix how to place them )

also zener etc

 

[Zen Mod]

gnd both inputs , no load on output

confirm what voltages you have at appropriate positions in orig schm ( you posted above)

 

[richluvsound]

Ok Zen


..... I had a 47K where it should have been 4r7 ..... only 90 % out ...

I have just wired it up and hopefully that was the issue !

I'll check the voltages after supper ...

Thanks , Richard

 

[richluvsound]

Got it .... I had the 47k and 4.7 k in the wrong place .... bloody eye sight ...


Thank you again , Richard