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Re: [PLAN_B_analog_blog] Re: PB 13 VC Attenuation

2008-03-25 by Eyesaw

Peter - That explains that! - Thank you, Bill
----- Original Message -----
Sent: Tuesday, March 25, 2008 12:05 PM
Subject: [PLAN_B_analog_blog] Re: PB 13 VC Attenuation

Anthony's giving prudent advice here.

First thing you ned to do is determine which physical lead you connect the various wires to. To do this, turn the pot shaft fully CCW and use a voltmeter or circuit beeper to determine which outer lead shorts with the center lead (wiper). Once you find that, call that shorted pot lead A

The Wiper (center lead) of the Pot is B
The other end terminal of the Pot is C

You'll also need to find the correct leads on the jacks. Depending on
what type you're using, there will be either two or three terminals.
Insert a patchcord into the jack and using a voltmeter or circuit
beper put one lead on the SHAFT of the patch chord and withthe other lead locate which jack terminal the shaft shorts to. This is the GROUND LEAD of the jack.

Repeat the process, this time putting one lead of the voltmeter/beeper
to the TIP of the patchord. This is the SIGNAL TERMINAL of the jack.

Wire as follows:

INPUT JACK SIGNAL TERMINAL to POT LEAD A

INPUT JACK GROUND TERMINAL to POT LEAD C and to the GROUND TERMINAL of
the OUTPUT JACK

Pot LEAD B to the SIGNAL TERMINAL of the OUTPUT JACK

There's a nifty way of getting ground to the pot without the need of a
buss power cable: take the ground form the ground terminal of the
input jack. The make sre it's also conected to the grounf terminal of
the outout jack as well.

hope this help-

- P

--- In PLAN_B_analog_blog@yahoogroups.com, Anthony Rolando
...> wrote:
>
>
> I would prefer linear taper in this application. Either should work
though.
>
> Wire the pot so that the leg the knob would point to when turned
full clockwise is attached to signal input. THe middle leg signal
output and the last leg connects to ground.
>
>; Tony
>
>
> > To: PLAN_B_analog_blog@yahoogroups.com
> > From: eyesaw@...
> > Date: Tue, 25 Mar 2008 12:52:14 +0000
> > Subject: [PLAN_B_analog_blog] Re: PB 13 VC Attenuation
> >
> >
> > Tried a 50k and did not hear much difference. Maybe I am wired goofy -
> > what are the proper connections from jacks to pot terminals?
Should this
> > be a linear pot and does the taper matter?
> >
> > Thanks for assisting the circuitry challenged amongst us - Bill
> >
>; >
> > --- In PLAN_B_analog_blog@yahoogroups.com, "(i think you can
figure that
> > out)" wrote:
> > >
> > > A passive attenuator is of course non-powered so the value of
the pot
> > > is much less important. Basically anything between 10K to 100K
is what
> > > you want. The higher the value, the less current is used.
> > >
> > > hope this helps,
> > >
> > > - P
> > >
> > >
> > > --- In PLAN_B_analog_blog@yahoogroups.com, "dingfutzer" eyesaw@
> > > wrote:
> > > >
> > > >
> > > > Peter:
> > > >
> > > > What would the correct spec be for a passive cv attenuation pot
> > > > for the LPG's? I plan on building my own 4x atten. module -
> > > >
> > > > Thanks, Bill
> > > >
> > >
> >
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
>
> __________________________________________________________
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