10 k reverse log to 5k, possible?

[JebemMajke]

I need a 5k rev log pot. And like I've said in a phase 90 topic it's not easy to find one in my country. And ordering online is out of the question. At least for now.
I have a 50 k rev log and a 10k rev log. How to convert ether one to 5 k? And to keep it as rev log.

[R.G.]

Not reasonable to do. Instead, use the 10K and scale the timing cap down by half.

[askwho69]

Not reasonable to do. Instead, use the 10K and scale the timing cap down by half.

wow now i know how thanks RG

[JebemMajke]

Not reasonable to do. Instead, use the 10K and scale the timing cap down by half.

But this thing is not for phase 90. It's for Zvex Box of Metal
So how to reduce 10k to 5k?

[R.G.]

But this thing is not for phase 90. It's for Zvex Box of Metal
So how to reduce 10k to 5k?

Again, not practical to do for all aspects of a pot.

I don't have the schemo for that circuit, but a lot depends on what the pot does in the circuit. If both the AC and DC natures of the pot are needed, it's quite tough to come up with a way around it. The schemes for making a wrong-value pot act differently depend on what it does. Tapering resistances may get you what you need for AC function, but they do funny things to the DC nature of the pot.

One way that works for the unique case of halving the pot value, like this, is to use a dual pot and parallel both sections. I don't suppose you have a 10K *dual* reverse log, do you?

[JebemMajke]

Nope, no dual rev log

Here is the schematic



I've seen guys using 5k log. But I would like to try it this way before trying to change anything.

[GGBB]

Is it for the gain pot?  The schematic I found indicates that it is used a variable resistor only, so I think you would be safe to parallel the 10K pot with a 10K resistor give you a 5K variable resistor.  It will affect the taper a bit but I don't know how much of a problem that would be.

[PRR]

> Here is the schematic
http://3.bp.blogspot.com/-5SZHOF-j-PQ/TxLFEH_WhuI/AAAAAAAAAiQ/XjoVO36zKIM/s1600/box_of_5shos.png

You have 10K Rev? Double R3 to 10K. Just tack it, you may want 8K or 15K.

This works because the ratio is more important than the absolute value; and the load on R3 (>1Meg) is much-much-much higher than any sensible value of R3.

[askwho69]

> Here is the schematic
http://3.bp.blogspot.com/-5SZHOF-j-PQ/TxLFEH_WhuI/AAAAAAAAAiQ/XjoVO36zKIM/s1600/box_of_5shos.png

You have 10K Rev? Double R3 to 10K. Just tack it, you may want 8K or 15K.

This works because the ratio is more important than the absolute value; and the load on R3 (>1Meg) is much-much-much higher than any sensible value of R3.

Wow... i dont know this also?? is the R3 used as voltage biasing? who it would affect the gain control? for me i will use 1k linear for the gain pot or use a crackle not ok schematic for the first gain stage... like this