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beautyofdecay_

Joined: Aug 14, 2009 Posts: 38 Location: Netherlands
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Posted: Tue Nov 02, 2010 1:32 pm Post subject:
BOM updated |
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I found 2 errors in the BOM.
You will need 6 4.7k resistors (not 3) and you will only need 2 ferrite beads instead of 6.
I uploaded the new BOM which you can download in my previous post. |
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camelneck
Joined: Sep 27, 2008 Posts: 65 Location: KY (USA)
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Posted: Fri Sep 07, 2012 9:53 pm Post subject:
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| TekniK wrote: | Done! did take me more time as expexted,If some one try it ,feedback is welcome.
Pdf contains PCB + parts implementation. |
I still see an error in the PCB layout. I believe that this module will work correctly once this error has been corrected.
When I first glanced at the 230 schematic I noticed two things that were a bit confusing:
#1) The right side of R6 connects only to the left side of R10.
It appears that Teknik has since fixed this problem on his revised layout.
#2) C2 connects to pin 1 of the op amp (not pin 2).
While the first issue was resolved correctly in Teknik's latest PCB layout, issue #2 has not been resolved correctly. C2 has been mistakenly connected to pin 2 of the op amp instead of pin 1.
If we assume that the schematic is correct (and I believe it is), C2 HAS to be connected to pin 1 of the op amp. Otherwise, the schematic would be wrong because it would imply that both inputs of the op amp (pins 1 & 2) are shorted together and there is no way the circuit would work properly if this were the case. (Teknik must have seen this problem and thought that the schematic was wrong, because the inputs aren't shorted on his layout.)
Unfortunately, I have not etched the PCB yet. Thus, I can't VERIFY that this correction will make the PCB 100% functional. However, for anybody who has already etched Teknik's revised version of this PCB and mounted the components on it, it is a very simple matter to correct this problem. Just follow these 2 simple steps:
1) Unsolder and lift the leg of C2 (100pF) that is closest to pin 2 of the 4136 IC.
2) Solder this now lifted leg of C2 (100pF) to pin 1 of the 4136 IC.
ALTERNATIVE: It may be easier to solder the lifted leg of C2 to diode D1, which is located right beside C2. Make sure that you solder the lifted leg of C2 to the leg of the diode that is connected to pin 1 of the 4136 IC. (This should be the leg of the diode that is closest to the lifted leg of C2.)
To fix the PCB layout,
1) Reroute the trace from pin 2 of the 4136 so it runs between the two solder pads for C2. By doing so, this trace will no longer be connected to one of C2's solder pads. (In fact, ths solder pad (for C2) will now be unconnected.)
2) Run a trace from pin 1 of the 4136 to the unconnected solder pad of C2. (This is the pad that pin 2 of the 4136 was previously connected to.)
3) Make sure that you repeat these same changes for the other 2 circuits on the PCB.
I honestly believe that fixing this problem will make this module functional because I didn't find any other problems. |
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n.d

Joined: Dec 15, 2011 Posts: 20 Location: Argentina
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Posted: Sat Dec 29, 2012 9:51 pm Post subject:
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So, camelneck, did you make it work?
Anyone? |
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oneoff

Joined: Nov 23, 2008 Posts: 33
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