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The recent M420 prescribed mod

2001-04-23 by John Speth

A few days ago I got my 255K resistors to update my M420 VCFs to remove the dead zone on the freq pot at low freq settings. I was just about to jump in make the mod and then it occurred to me that the pot actually *needs* a dead zone so that DC levels at the FM inputs would not severly limit the lowest freq setting of the pot.

My question is: Wasn't this dead zone intentionally designed in? Seems like a classic design tradeoff issue that has now been forgotten.

Can anyone tell my why making the mod is not a no-brainer?

John Speth mailto:johns@...

Re: [motm] The recent M420 prescribed mod

2001-04-23 by Paul Schreiber

Well, not 'intentional'. It's just a matter of do you want the '0' tick mark to be DC or like 8Hz. I use 243K, 255K is fine.

Paul S.

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----- Original Message -----

From: John Speth

To: MOTM List from Yahoo (E-mail)

Sent: Monday, April 23, 2001 4:05 PM

Subject: [motm] The recent M420 prescribed mod

A few days ago I got my 255K resistors to update my M420 VCFs to remove the dead zone on the freq pot at low freq settings. I was just about to jump in make the mod and then it occurred to me that the pot actually *needs* a dead zone so that DC levels at the FM inputs would not severly limit the lowest freq setting of the pot.

My question is: Wasn't this dead zone intentionally designed in? Seems like a classic design tradeoff issue that has now been forgotten.

Can anyone tell my why making the mod is not a no-brainer?

John Speth mailto:johns@...

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