Creating a Custom Cable: 7-Pin Amphenol Connector and Unique Electrode Input

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Ephant
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This cable costs $200 so I want to build one. I know where to get the round silver plug at right which is a 7 pin Amphenol and I know the pin designations inside.

I'd like to know if the left white electrode input socket can be found anywhere or it can only be made special at factory. Have you seen anything like it being sold anywhere?

The red (+) and black (-) input is differential with a ground/reference at middle. Should I use twisted wires like used in ethernet cable as the cable? What is the size of wire I should use. How many feet before it can cause enough noises?

I plan to use up to 1000 Hz signal. If the wire and plugs at either end is not matched. Would the impedance mismatched attenuate or cause noises in the signal?

Thanks!
 
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Ephant said:
Have you seen anything like it being sold anywhere?
What are the physical dimensions of the shell and the electrodes?
Ephant said:
The red (+) and black (-) input is differential with a ground/reference at middle. Should I use twisted wires like used in ethernet cable as the cable?
Twist the (+) and (-) wires, and shield them inside the grounded screen.
Ephant said:
What is the size of wire I should use.
That depends on the unspecified signal amps, the voltage determines the insulation.
The wire should fit in the shell, and terminate sensibly at the electrodes.
Ephant said:
How many feet before it can cause enough noises?
Many. At 1 kHz, a screened twisted pair will be reasonably quiet. How much noise do you need to avoid, and in what environment?
Ephant said:
I plan to use up to 1000 Hz signal. If the wire and plugs at either end is not matched. Would the impedance mismatched attenuate or cause noises in the signal?
The wavelength of a 1 kHz signal would be 3e8/1e3 = 3e5 = 300 km. The cable is very much shorter than that, so there should be no problems at 1 kHz.
Only the total lump capacitance of the cable would be important.
 
It's 1.5mm Touchproof sockets. Voltage is biopotentials of human skin surface. So I can just use ethernet cable?
 
Why do you suppose it costs $200? What-all does it do? What does it plug into?
 
Because this appears to be related to the OP's DIY Biomedical experimentation, the thread will remain closed.