Signal Board for PFC v.2


Here is the PCB we received from MACROFAB

We did not have time to test it yet, but it looks good. Will post more about the integration when we have a moment.


I have been working on getting signal board in place and after extracting BOM from eagle, I am not clear on some of the components which are listed below.

Would be really helpful if someone can throw more light on the following components in the signal board schematic and what is the use.




Any chance you could post the .bor file or upload it to Github I don’t see it in the list of files for Gerber or Eagle. I get the same issue with ~100 parts not populated in MACROFAB.



@ekoziol I ended up doing without the .bor file and re-placing my order again using the eagle file available in github directly. I had to cleanup the BOM after the import of the eagle files on their website too. I’m attaching the updated BOM Macrofab used for my order.

The original extension is .xyrs, but I had to rename it to pdf to attach it to this post. I hope it helps.
9q6defg-1.xyrs (6.2 KB)


@francoisnyc Thanks! This is exactly what I needed. I converted the file in sublime text and uploaded it to MACROFAB. It works perfectly!

@spaghet I’ve initiated a pull request here with the updated file:

For future users, this change is for those that wish the build the signal board through Previously, uploading the eagle schematic and board files would not populate all of the components. The new .xyrs file handles all placement and components of the board that actually need to be attached. Users will now have to upload the .sch, .brd, and .xyrs files to have the proper setup. It will result in 4 unique parts not being populated, for a total of 10 parts (PAD070, ATLAS_SCIENTIFIC_STAMP, ARDUINO_MEGA_2560_R3_CONNECTORS, and ARDUINO_UNO_REV3_SOCKET). You should have 85 total parts on MACROFAB.


Hey guys

Me and my friend are building the PFC v.2 in Switzerland. We are both not really into programming and understand just a little of what you are talking about in this thread.
My question:
Would it be possible that someone of you guys would help us to place the order for the Signal Board, or that we could place the same order like someone did it in advance? Because I’m a bit afraid that we aren’t able to do it by our own.


Hello @Bataleon7! Great to hear! We offer nearly fully assembled Signals PCBAs on our website here: and we indeed do ship to Switzerland! Happy Farming!


Hey @iancollmceachern

Thanks for the information. We saw your product. what means nearly fully assembled?

We are both students, and were hoping to find a cheaper way to get it produced.



Hi @Bataleon7
Thank you for the great questions!
By nearly fully assembled we mean that all the difficult to solder components have been done, SMD devices and most thru hole parts as well. The only items left for you to solder yourself are the Male Pin Headers that connect it to the Arduino, the headers that connect to the Atlas Sensor Daughter Boards, and the pin headers that connect to the ribbon cable. If you have ever soldered the 20 pin header onto a raspberry pi zero, or the headers onto an arduino shield then you have done what is needed.

As far as cost goes, the standard price on our website for the nearly fully assembled PCBA is just barely over our cost to produce them. We also offer academic discount which we give to all students and schools - please email me at for the coupon code. With the academic discount we actually sell the PCBAs at a loss.

Put another way - our Signals PCBA with the academic discount is sold for less than it costs us to make them.

Happy Farming!


Okay, I have a question that is probably stupid, but I’ve just been wondering. Is it possible to build a PFC without the signal board? Since the signal board connects to the Arduino, and then all of the other components are connected to the signal board, can’t we just connect all of the components directly to the Arduino?


You can build the PFC V2 without the signal board. You will need an Arduino Mega 2560. In lieu of the signal board you will need to wire all the sensors and actuators to the appropriate Arduino I/O using your chosen method (jumper wires and/or Arduino shields). The signal board also provides voltage isolators for the Atlas probes. So you will need to provide something like this ( for each atlas sensor. I wanted to build my system on the cheap so i bought a bare board from Ian and then bought the components separately and soldered the board myself. No matter which route you go there is a lot of labor involved and I doubt any vendor has automated signal board production so that the labor cost has been netted out resulting in a low cost source. Also keep in mind that the Open Ag team may have moved to the Beagle Bone Black which means the Arudino Signal board may become an orphaned technology.


I thought I saw something about potentially using a Beagle Bone Black as the central brain for the PFC. The primary reason I could see them doing that is that it would enable them to create an single board that could host the majority of the electronics. However, the lack of CPU power would be a huge limiting factor. I also think that serial connection between Pi and arduino has caused many problems. Personally, I’m just not sold on using ROS for the PFC because it’s seems overly complicated and not good fit for the need/use of the PFC.


Hey there - thanks for producing the signal board - I’ve been struggling on this and appreciate the short cut! :wink: . Are shipping costs any different if it is shipped to Canada (Toronto) or New Jersey?




HI @Mark, gladly! The shipping cost is $15 to any US address and $35 to any Canadian address with other internal shipping charges are different per each country, typically $55 or so.

Happy Farming!



Thanks for the info - ordered!


Wonderful, I just saw it come through - thank you for the order & Happy farming! We will get going on your order right away.