DIY: automated linux-assisted hardware testing

a new milestone for me: I threw together some C code, shell scripts, cables and test gear in order to see how linear my relay attenuator (for audio) is.

 

link to my write-up on how I did all this:

 

www.amb.org/forum/automated-testing-of-delta1-steps-t1752...

 

the fluke shows 17.44dB measured and my LCDuino says it should be 17.5dB. that's .06dB error on this step. not bad, huh?

 

with 50v put into the attenuator, the fluke reads 6.728v out. I have the fluke setup to read both relative dB and absolute volts in its two displays (and also on its serial port).

 

a typical fluke line would look like:

 

-17.44 +6.7275

 

or

 

-125.42 +0.027E-3

-126.02 +0.025E-3

-126.33 +0.024E-3

-127.00 +0.022E-3

-127.18 +0.022E-3

 

as we get closer and closer to 127.5dB attenuation (the most this relay board can handle).

 

 

(not all the equip shown was used; but if it had its display on, it was part of this test) ;)

 

Done