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Old 26th April 2014, 09:19 PM   #341
agdr is offline agdr  United States
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Quote:
Originally Posted by adydula View Post
First mechanical fit issue, D16 1 amp 400v 1N4004GP E3/E4 diode doesn't fit in the hole for D16. D15 is ok, its a smaller dia set of leads on that diode (1N5260B-TR).

Same for D3, D4, D5 and D6.

Will try to open up with a small drill or "sand" down the diode leads carefully etc.

Alex
Alex, it sounds like you have your diodes swapped. D16 is the 1N5260B zener in the smaller DO-35 case, while D15 is the 1N4004 in the larger DO-41 package. Probably best not to drill the board right there - if swapping the diodes don't solve it please PM me and lets discuss. ALSO - I did have a larger 1W zener in for D16 in an earlier version of the BOM and changed that to the current 1/2W. That larger one (different part number) won't fit. If you ordered that by chance off an older BOM, let me know. I have a pile of the 1/2W here. That goes for anyone else building on this set of boards too - if you ordered the wrong zener diodes for D16 just let me know and I'll send you replacement no charge.
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Old 26th April 2014, 10:29 PM   #342
adydula is offline adydula  United States
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Hey I sent you a PM.

Here is the best photo of the zener in D16 band down and the larger fitting 1N4004 in D15.

Alex

Note the only 1N4004 diode I have installed is the one in pix D15, I had to take an emory board and ever so gently file down the leads to get it in the holes....np. So its not the wrong zener etc..
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Last edited by adydula; 26th April 2014 at 10:41 PM.
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Old 27th April 2014, 12:36 AM   #343
adydula is offline adydula  United States
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I looked at the mouser site for the 1n4004 diodes and the part number in the BOM is for the DO-41 package...so it looks like the holes in the board itself are just too small for this DO041 package lead size...

Alex
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Old 27th April 2014, 01:12 AM   #344
agdr is offline agdr  United States
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Quote:
Originally Posted by adydula View Post
In the build instructions page 10, where it says "So these are IC11, R70, R79, R83, R84, R85, C49, C50, C61"...

C61 is part of the Zorbel network...so this probably should not be in this list?

Also not on the schematic, near the Zorbel network, there is a note that indicates the parts to be left out R78, R79, C74 and C75, are these correct??
(the build instructions have R86, R87, C60 and C61).

Alex
Good finds! You are right on both counts. In addition there was some wording about the damping resistor positions that needed to be updated on the schematic. Both are fixed and a new set of build instructions and schematic are posted out at the Google Drive link. BTW, I can't remember if I've mentioned this, but credit goes out to Limp for sharing the secret of getting Eagle to dump nice sharp & scalable vector schematics! Use the print and print as PDF rather than going the export -> image route.


Quote:
Originally Posted by adydula View Post
I looked at the mouser site for the 1n4004 diodes and the part number in the BOM is for the DO-41 package...so it looks like the holes in the board itself are just too small for this DO041 package lead size...

Alex
Well this has certainly been an interesting find. It would appear that you are right. In the photo build that I did the 1N4004's were one of the few parts where I used a bunch I had on hand rather than the Mouser part I specified. I did get some of those Mouser diodes in though last week and just tried one in MisterRoger's boards that I still have here. Sure enough, doesn't fit. Not sure what exactly is going on there yet, probably an Eagle library error, but there is an easy fix. I have a big pile here of the ones that do fit, so I'll simply send a set out to everyone, no charge of course. Problem solved for this build, and I'll get the Eagle issue corrected before the next board run.

Good find! I'll get those diodes in the mail to everyone on Monday.

Last edited by agdr; 27th April 2014 at 01:23 AM.
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Old 27th April 2014, 01:33 AM   #345
adydula is offline adydula  United States
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T

Thanks very much....great DIY customer service for sure!!

Alex
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Old 27th April 2014, 12:06 PM   #346
agdr is offline agdr  United States
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Quote:
Originally Posted by adydula View Post
T

Thanks very much....great DIY customer service for sure!!

Alex
I've found the problem. When I created that vertical 1N4004 part library I somehow screwed up and used DO-35 sized pads. Then I never noticed the problem because the pile of 1N4004 and 1N4006's I have on hand just happen to have leads sized at the lower end of the 0.072mm - 0.86mm range for DO-41 and fit just fine. Murphy's Law is still aliive and well.

The other few vertical diodes on the board are zeners and really are DO-35, so all is OK there.

I have the problem fixed now and I've re-posted the Gerber files out at the project Google Drive link. I'll mail out those diodes on Monday. Thanks again to Alex for finding this one!

Also - I wanted to say thanks to MisterRogers for letting me move him to the next board run list. I've decided to keep a board or two on hand to use for more detailed build photos (higher rez).

Last edited by agdr; 27th April 2014 at 12:08 PM.
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Old 27th April 2014, 04:35 PM   #347
adydula is offline adydula  United States
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Ok Assembly Step 1 completed...

Including the 12 balancing resistors.

Less the "optional" C62, C63 HF Bypass caps across the electrolytics C7, C8.

Now I must wait for the ac adapter from mouser which has shipped and test the CRC part!! (JP8, JP9).

First Pix: Here is the board in my "Vise" its a really heavy drill press vise that doesn't move around much, very stable and allows me to angle if needed.

Second Pix: Top View so far...

Third Pix: Bottom Board

Fourth Pix...looking pretty!! LOL

Alex
Attached Images
File Type: jpg CAM00086.jpg (494.9 KB, 91 views)
File Type: jpg CAM00087.jpg (447.9 KB, 86 views)
File Type: jpg CAM00088.jpg (416.8 KB, 80 views)
File Type: jpg CAM00085.jpg (638.8 KB, 79 views)
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Old 27th April 2014, 05:20 PM   #348
Turbon is offline Turbon  Sweden
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Yes, pretty enough ...

I got to get serious abt this and until funds allows I can create the order

Regards
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Old 27th April 2014, 05:48 PM   #349
adydula is offline adydula  United States
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Turbon,

I can understand the part about funds...I was layed off last October from the Lenovo PC Company. I am 64 yrs young and have gone thru many resource actions are they are called now....train people from China and then watch your job go away and then hey thanks great job but your function is no longer needed here....

Enough whining!! LOL

I decided to retire...and now have lots of time to do projects etc but all things are on a fixed budget here!!

The ODA is not an inexpensive DIY for sure, The parts, case and AC adapter brought this project up to the $250 area.

I think the end result will be worth the time and effort. Agdr has done a really awesome engineering effort on making this ODA a reality.

I really enjoyed building my O2's and am enjoying the ODA build so far.

My back ground is a electronics technican/engineer for 30+ years, done lots of troubleshooting and debug with AC/DC and RF circuits. Had my shares of getting shocked!! I never was in the design part but worked a lot in circuitry to be able to debug things when they are broke!

I had my order in Mouser's project area for a few weeks and sold some headphones I had to fund the project!!

I am waiting on the 24VAC 1/8 amp xfmer from Mouser which by itself in $30! The case is $20 or so as well....

Copper prices and shipping costs all add up now-a-days.

Hope you can get started soon!!

All the Best
Alex
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Old 28th April 2014, 02:16 AM   #350
adydula is offline adydula  United States
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Well I just found my first mixup...no power Yahoo, but FYI there are three sets of SMD resistors that are very similar if your not careful identifying...I just had to remove R78 and R82 which wasn't as bad as I thought it would be...at least the parts didn't go flying across the floor and they weren't hurt in value removing them..

So: R78 and R82 are 499K Relay delay resistors
R8 and R12 are 499 ohm 4x gain resistors
R42 and R43 are 4.99K input bias gnd resistors..

So...its easy to overlook and pick the incorrect ones!!
even checking with a meter before and after installing I missed this.

I was identifying the remainder resistors and labeling them with there respective R numbers and came across 2 that I thought I had already installed!!

oh my.....64 yrs old and half blind...

LOL

Alex
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