'Z' Taper calculator???

[ihscoutlvr74]

Gents,

I'm finishing up with an 1176 and read the best input attenuator is a 3 deck potentiometer - 2 500ohm and a 1k Z taper pot.  I've got some 12 step, 3 deck mbb grayhill rotary switches and was curious if there is a calculator somewhere for the Z taper resistor values?

Many Thanks, Nathan

 

[Mark Burnley]

Hi,

Z-taper = Logarithmic

Check out graph to left of page 5 on this pdf

Hope this helps,

Mark

 

[shabtek]

you can do this with a 2 deck switch.
t-pad calculator
http://www.m0ukd.com/Calculators/Attenuator_Calculator/T_attenuator.png
http://www.m0ukd.com/Calculators/Attenuator_Calculator/T_Attenuator_Resistor_Calculator.php

bottom of r2 is grounded signal in on 1 pole of switch, signal out on the other pole
pad connected to the throws of the switch.
jumper the highest throw position for no attenuation

or search for nyd attenuator

 

[abbey road d enfer]

Gents,

I'm finishing up with an 1176 and read the best input attenuator is a 3 deck potentiometer - 2 500ohm and a 1k Z taper pot.  I've got some 12 step, 3 deck mbb grayhill rotary switches and was curious if there is a calculator somewhere for the Z taper resistor values?

Many Thanks, Nathan

When replacing pots with switches, you don't have to obey the constraints of potentiometer manufacturers. You can calculate the whole attenuator for your exact requirements.

 

[Mark Burnley]

Yea,

I'd just find what levels you need to deal with and pick those spot values.

It's pretty tough trying to "emulate" a pot rotation.

I usually use -3/-6/-10 dB as useful step levels, depending on how much you need.

Mark