[DolbyR]

Hi Guys.
I've just got from ebay a stepped attenuator "kit" this doesnt come with instruction so I need bit of help. The selector is almost exactly as here http://www.diyfidelity.com.au/produc...products_id=32 so I'm using this as guidance.
But I just can't figure out how do I know which pins are for which position of the switch?

 

[JamesL]

Alright, so first, it looks to be a ladder attenuator, meaning for each of the 23 'steps', there is one resistor connecting from input to output, and then another one from output to ground, to create a typical voltage divider.

sorry about the shabby image.. =x

 

[DolbyR]

thats clear, thanks.
So I guess I should just multimeter it somehow to find out which pins/resistor places are for which positions of the switch.

 

[DolbyR]

Mine is 99% like this one

The only difference is the placement of the row with more pins, if you look well, the one marked as position 1 has double the pins of the other rows (the same thing in the side where is the other screw). Well on mine, this row with more pins is on the place where is marked "2" in the picture, and this is mixing me. How can I measure the pins to know the correct pins for the respective positions?

 

[JamesL]

Hm. That's weird that the output pins would be in the second column.
Try this.
Turn the knob all the way clockwise to pin 24, and do a continuity test between pin 24, and the corresponding "extra pin" on the other side.

 

[DolbyR]

Yepp, I get continuity there, also starting from pin 1 and turning the shaft, I get continuity on that "extra" pin on row two and the corresponding other pins. So it looks like the pins are the same order as on that picture (after all its the same blue selector) maybe theres a manufacturing error and for that reason the guy in HK is selling them that cheap ... 9 bucks for the selector and resistors.