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DIY Resistance Box

Pexy

Feb 21, 2016
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Hi Guys. I am on a path of of buying parts for my DIY resistance box so i was wondering is a Decade resistance box better than a Potenciometer one and vise versa? What would the benefits and down sides be of one and other?
 

(*steve*)

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A decade resistance box is easier.

If you want a potentiometer, google "Kelvin varley potentiometer".
 

shrtrnd

Jan 15, 2010
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If you go with a decade box, it would help you to try to use low tolerance ( 1 or 2%) resistors, and at a wattage rating appropriate for the types of circuits you expect to use it in.
I don't know what you expect to use this for, but a potentiometer will require monitoring to know when you reach whatever resistance value you want with accuracy.
 

(*steve*)

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I have a precision divider (a type of potentiometer) that I use fairly regularly.

It's a bit specialist in nature, and I tend to agree with Colin about not using a substitution box (although I don't own one).

Sure you may use it, just be aware of how it may differ from a simple resistor (series inductance and parallel capacitance). These may not be important for your circuits if they are audio frequency.
 

Pexy

Feb 21, 2016
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I have a precision divider (a type of potentiometer) that I use fairly regularly.

It's a bit specialist in nature, and I tend to agree with Colin about not using a substitution box (although I don't own one).

Sure you may use it, just be aware of how it may differ from a simple resistor (series inductance and parallel capacitance). These may not be important for your circuits if they are audio frequency.
Ok thanks
 

elebish

Aug 16, 2013
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Hi Guys. I am on a path of of buying parts for my DIY resistance box so i was wondering is a Decade resistance box better than a Potenciometer one and vise versa? What would the benefits and down sides be of one and other?
If you are not using it for frequencies above 30 KHz, a box will be better. A pot is usually a half watt which is not very high and there will also be insertion loss containing capacitance and inductive reactance affecting your circuit depending on frequency. A wirewound pot would be the worst at the higher frequencies. Use fixed carbon film resistors when possible.
 

Pexy

Feb 21, 2016
142
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If you are not using it for frequencies above 30 KHz, a box will be better. A pot is usually a half watt which is not very high and there will also be insertion loss containing capacitance and inductive reactance affecting your circuit depending on frequency. A wirewound pot would be the worst at the higher frequencies. Use fixed carbon film resistors when possible.
Ok thanks
 
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