Daisy recommended SRB connections?
Hi, community.
A while ago I set up my OpenBCI like so:
Recently I have discovered that the 8 channel setup is very rough and that the 16 channel provides a lot more fidelity and there are things that the 8 channel setup does not pick up while the 16 does.
But the default tutorials did not cover how to set up the daisy module and connect it. I suppose it`s pretty straight forward, but I have failed in my searches to find what exactly is needed to provide a uniform reference/bias to both bottom rows of the both modules. I should need some kind of a double-pin female connector that I can plug the male reference clip wires into? Or must I have separate clips for the daisy module? I do not know how to name the splitting connector and how to search for it. =/ Iterating, I believe that the 9-16 channels are all plugged into the daisy module in a symmetric fashion as on the main board, yes?
Thank you for reading.
Comments
See this thread,
http://openbci.com/forum/index.php?p=/discussion/575/ch-1-8-ok-ch-9-16-railing
You need to make a Y-cable to connect the SRB2 references.
You also write:
> Recently I have discovered that the 8 channel setup is very rough and that the 16 channel provides a lot more fidelity and there are things that the 8 channel setup does not pick up while the 16 does.
The reverse is actually true. 8 channel runs at 250 sps, 16 channel at 125 sps.
William
Look at these,
https://www.adafruit.com/products/825
They are male to female jumpers. Take two of them and cut each of them in half. Strip the ends with a wire stripper. Now take two of the females and one of the males. Hold the stripped ends together and twist them. If you have solder, solder them. Wrap the exposed twisted section with tape of some sort, or I guess you could use a wire nut also. Now plug the two females on the SRB2 (closest to board) ref pins. Plug your cup sensor into the male. Done.
re: time and space resolution.
Yes more channels are helpful for applications that need them. Such as QEEG or source localization. But a tremendous amount can be done with just 8 or less channels. The signal from a single surface electrode represents ensemble synchronous activity from a large area of cortex. I've heard Nunez quoted as something like 5 square centimeters. To do QEEG or source localization typically at least 19 channels are needed; 32, 64, 128 are used in clinical / medical / research applications.
William