The Fender Delta Tone System, Pt. 2

Let’s take a closer look at no-load pots.

In my previous column, we

began a two-part series on

Fender's Delta Tone system,

which includes “no-load" pots.

After introducing the Delta Tone

in 1997, Fender made it a feature

of the American Standard

Stratocaster, and the system

is still in use today. For a full

description of the Delta Tone

system, check out the January

2011 installment of Mod Garage

on premierguitar.com/jan2011.



Now, let's take a closer look

at no-load pots. Visually, it's

easy to identify a no-load pot,

because of the detent dimple on

the back of its enclosure. This is

the mechanical spot where the

pot clicks and goes completely

open, removing itself from the

circuit. Other than having this

dimple, a no-load pot looks like

any other guitar potentiometer.



The CTS no-load pots that

are available from Fender aren't

very expensive, but if you like

the tone pot you already have

and don't want to replace it,

it's not difficult to mod it to

no-load specs—that's assuming

you can live without the detent

function.



Here's how to do it. First,

unsolder and remove the pot

you'd like to mod. The next step

is to disassemble the pot. Using

a pair of small needle-nose

pliers, start this operation by

bending the pot's case tabs open.

Next, remove the metal housing

and lift out the carbon wiper

tray with the soldering lugs.

Place it in front of you exactly

as shown in the photo shown

here. Though your potentiometer

might be a little different, it

should look similar to this one.



Now take a sharp razor

blade, X-ACTO knife, drill bit,

Dremel tool, or a small needle

file and cut the trace, right at

the red line shown in the photo.

Personally, I like to use a special

file made for guitar nuts for this

work, but you can use whatever

you have at hand. Scrape

off approximately 1/8" of the

carbon and clean this area with

a dust brush or a similar tool.

That's it.



Next, reassemble the pot

and use the needle-nose pliers

to push back each of the four

case tabs. Reinstall the pot on

the pickguard and resolder the

wires. Voilà! With the pot fully

opened, it will remove itself

from the circuit. Now you have

a no-load pot without any additional

costs . . . but without the

detent feature.



A side note: You might read

that covering that area on the

carbon wiper tray with nail

polish will do the same trick as

scraping off 1/8" of carbon. I

don't recommend this, because

depending on the pot, the polish

may not stick to the carbon

taper. The “surgical method"

outlined here is better.



To test your no-load pot,

turn your pot so that the shaft

is facing down and the lugs

are facing up, and connect one

lead of your digital multimeter

(DMM) to the middle lug of the

pot, and the other lead to the

right lug. Next, set your DMM

to resistance. With the pot

turned all the way clockwise to

10, you should receive an open

or “no reading." If you turn

the pot counter-clockwise to 9

or lower, the pot will function

normally, and you should see

readings that are close to the pot

value and that decrease as you

roll back toward 0.



Stay tuned for more Strat

mods in the coming months.

Next time, we'll talk about the

Fender “Greasebucket" tone

control. Meanwhile, keep modding!




Dirk Wacker lives in

Germany and is fascinated

by anything related to old

Fender guitars and amps.

He plays country, rockabilly,

and surf music in two

bands, works regularly as a

session musician for a local studio, and writes

for several guitar mags. He's also a hardcore

guitar and amp DIY-er who runs an extensive

website—singlecoil.com—on the subject.

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