Big day. Big win. Big upgrade.
Got the mass flow controller online!
First we got a +/- 15V power supply on eBay for $30:
Real nice Lambda. 3.3 Amp.
Wire up the AC side:
Solder the pins on the 9 pin Dsub – data cable on the left, power on the right:
The MFC draws 60 mA. The MFC’s pinout:
Physically install the MFC:
This required a female to female VCR fitting seen to the right of the MFC. It’s pretty securely connected with just the VCR. Stuart suggested installing the MFC upside down to reduce the chance of knocking it downward.
Here it is fully installed:
And it works! First try. Here I have adjusted the chamber pressure to even numbers:
When I am running at full flow, the chamber reads 1.9 e-2 torr.
[…] computer control I needed some way to manually adjust the MFC. I hacked together a quick voltage divider using a 2KΩ potentiometer and a 9V […]