sontec 1 RU build thread

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I've finally decided to get to work on my Sontec.  Before I pull the trigger on any orders I had questions about some of the BOM items.

Red flags are in red.  My questions/comments are in green.

BTW, does anyone have a USA BOM going for this project?  I'd like to compare parts and prices with what other folks have found.

Thanks!

slowbass said:
I asked Igor and he sent me this bom (bom_sontec.doc) I've just changed the quantity of the pots from digikey : 1 x 5K lin potsw and 3 x 5k lin pot instead of the contrary. There maybe a resistor missing for the amp pcb. I hope it's ok to copy it here.

BOM  for 1 channel!

CONNECTORS

2 MOLEX 3 PIN (NOT USED WITH NEUTRIK CONNECTORS)
2 MOLEX 5 PIN
3 MOLEX 4 PIN 3.81 PITCH
1 OUT CON-NEUTRIK_AG_NC3.
1 IN CON-NEUTRIK_AG_NC3

^ Anyone have a part number on the Molex parts?

POTENTIOMETERS

1 5K LIN POTSW  (instead of 3)
http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=CT2204-ND

3 5K LIN POT (instead of 1)
http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=CT2226-ND

Links seem to be backwards.

CAPACITORS-ELECTROLYTHIC
2 100U CPOL-EUE5-10.5
2 100U CPOL-EUE5-13
CAN BE 100-470 UF 35-50V, POWER SUPPLY BYPASS CAPS

^Should these be Bi-Polar or will non-polar electrolytics work?

4 33U CPOL-EUE5-6
USE 33U 25-50V HIGH QUALITY TANTALLUM OR AUDIO GRADE ELECTRILYTHICS


CAPACITORS-CERAMIC

17 0.1U 5MM PITCH CERAMIC POWER SUPPLY BYPASS
' VALUE CAN BE 0.047-0.33 UF 50V


CAPACITORS-POLY ETC.

1 0.15U C-10-15/6
2 0.47U C-10-15/6
8 1U C-10-15/6
1 2U2 C-10-15/6
1 1U C-10-15/6
2 2u2 C-10-15/6

1 4u7 C-10-15/6 (PITCH UP TO 35MM, POSSIBLE TO USE 2 CAPS IN PARALLEL)
1 ** C-10-15/6   What the hell is this??
 
MikoKensington said:
I've finally decided to get to work on my Sontec.  Before I pull the trigger on any orders I had questions about some of the BOM items.

Red flags are in red.  My questions/comments are in green.

BTW, does anyone have a USA BOM going for this project?  I'd like to compare parts and prices with what other folks have found.

Thanks!

pot with switch; you only need one per ch (lo-pass filter section)

power supply bypass caps etc caps are all polarized caps... get conformation from Igor,  if non-polar would work there...
(isnt bi-polar and non-polar same thing btw ?)


C10-15/6 means Cap; pitch 10-15mm / no idea on after slash
330P C7.5/3 means pitch 7.5mm
150P C5/2.5 means pitch 5mm
 
kambo said:
pot with switch; you only need one per ch (lo-pass filter section)

Yes, I know.  But the links in the BOM are backwards on the "Edited" version.  So if you order from that you'll end up with the wrong quantities.  I was making a note for future builders.

kambo said:
power supply bypass caps etc caps are all polarized caps... get conformation from Igor,  if non-polar would work there...
(isnt bi-polar and non-polar same thing btw ?)

I meant polar or non-polar. 

kambo said:
C10-15/6 means Cap; pitch 10-15mm / no idea on after slash
330P C7.5/3 means pitch 7.5mm
150P C5/2.5 means pitch 5mm

I get all that, too.  The section I have in red, has no value.  I'm just trying to find out where and what that is. 
 
sorry, my mistake,  "My questions/comments are in green"... i couldnt distinguish your comments from your questions... all sounded like question to me :)
anyway,
1 ** C-10-15/6 What the hell is this??
a parallel cap,
so the value would be calculated by you, to be able to get 4u7
 
Ah ha!  I thought that could be the case, but the note on the BOM was before that mystery cap.  Thus confusing me terribly.  :D 

Thanks Kambo!
 
Hi all,

I have just finished my GSSL and am thinking of doing this as my next project. I will be using a Tat Purusha case. Just wanted to ask if there was anything that is very hard to source or any other gotchas in the project?

The only BOM I've been able to locate is this one: http://www.groupdiy.com/index.php?topic=27972.msg437569#msg437569 and I can't seem to find a store for the correct pots here in europe? Also, Igor has recommended 2604 and 604's as the opamaps with Forssell JFET-993's on the summing. Anyone built one with this setup?

Thanks
 
www.alphastat.de and digikey for pots;
I used 800 mA SB fuse for local 230v with 25VA toroid.
 
Rotational Angle
Total Rotation
Without Switch: 300° ± 5°
With Switch: 315° ± 5°
Effective Rotation
Without Switch: 300° (approximate)
With Switch: 290° (approximate)

This quote is pulled from the CTS 270 pots datasheet.
Could someone explain what's the difference between "total rotation" and "effective rotation" ???
For home front pannel designs , what degree did you use for tho pots ?


Thanks.
 
hey guys - i'm finally starting work on my sontec... have a set of the older run boards (v1.6 - the green ones).

does anyone know if there are any errors on the silk screen component values? or can i just stuff as per what's shown on the boards?

also, anyone had good/bad experiences with any types of capacitors in the sontec? i'm thinking i'll put in a wima order from TAW - polypropylene when they will fit, otherwise metallized polyester...

thanks mateys!
 
Change summing resistors (10 and 20k) to twice higher. It will give 6db range.
You can do a on-off-on swich for every band to get 12-0-6 on it.
 
Igor said:
Change summing resistors (10 and 20k) to twice higher. It will give 6db range.
You can do a on-off-on swich for every band to get 12-0-6 on it.
OK, never thought of making it switchable.. nice idea!
So basically 20k on the summing buss will give 6db range and 10k (7k5 on the schematic) will give 12db range?
I mean, the resistors are on the cut and boost buss in series with potmeter.
 
i think Igor means the summing resistors, far right on schematic, (separated  small schematic),
thats where i placed my switches for 0-12db...
 
OK, so if i understand it correct, the 20k resistors should be 40k for 6db and the 10k (for hi band that is) should be 20k for 6db range.
sontecsum.jpg
 
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