Bonsai’s X-Altra MC/MM Phono Preamp

Here are a few errors I found:
1k resistors, the BOM says 2, 8 are needed
OPA 1641, BOM says 6, 4 are needed
LM4652, BOM says 3, 4 are needed
22uf 35V capacitors, BOM says 6, 4 are needed

BOM does not have the 120ohm, 110k ohm and 150k ohm resistors anywhere. The ones placed near the DIP switch, I don’t have the boards with me atm to check board reference.
 
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I have attached newly updated and checked BOM to the first post in this thread. I will leave this there until your builds are done so that if you have any further inputs, I can make those before putting the correct BOM up again on the audioXpress hosted website again, which will then be the master BOM moving forward.

Here is what I think happened with the BOM that has caused your grief. I had quite a few copies of the BOM on both my desktop and my laptop and in the Microsoft Office cloud storage service that I use. I think during the update late last year, multiple copies of the BOM were open across all three places and when I packed everything up into a zip file to send to aX, ended up somehow corrupting the BOM. I'm in the process of deleting all extraneous copies to avoid a repeat of this.

Again, my very sincere apologies for this. Any questions/input, please let me know.

Regards

Andrew
 
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Thank you for all your hard work, dedication and determination on this, Andrew. I know from personal experience how difficult it is keeping a BOM current (as things reach End of Life, Obsolete, etc.). And to complicate things further, your builders are from various countries and availability of some items can be different based on local suppliers.

The PCBs arrived today. I will probably begin my build in early October. All the items with a long lead or shipping times (like the Talema transformer and the ModuShop chassis) have been secured and are sitting on the bench along with all the necessary tools. A fresh batch of solder paste for the hot air gun for the SMDs is waiting for me in the refrigerator. And I finally figured out that "screened cable" (U.K.) is what I know to be "shielded cable" (U.S.). 😉

-Jon
 
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Hi.

Construction continues. Now I'm waiting for the transformer. And then inspection, measurement and complete completion.
Yeah, I still have to buy the box on the Modushop website...

JL
 

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