I know there are at least a few participants here who have guitars, so I was
wondering if anyone here has attemped a Ringer Test (inductor Q) on guitar
pickups.

I haven't tried the pickup in a guitar, so I don't know if it plays OK, or
not. I disassembled it to install a 4-conductor shielded cable (with coils
split) instead of the single coax lead (coils wired in series).
The combined DC resistance of the 2 coils is about 13k ohms.

I have a used Epiphone humbucker here which I removed the cable from, and
figgered I try ringing the coils (separately) with a Sencore Z-Meter LC77.

I remembered that the Z-Meter manuals specifically state that these testers
work with inductors with powdered iron/ferrite-type cores (not steel such as
power transformers), so I removed the steel screws, but the coils still only
have 4 rings.

So the bobbins are removed from the frame plate and magnet, and have no
screws in them.. which should just be a plastic bobbin with hundreds of
turns of very fine wire on them (one turn would be ~5").

The wire size is probably about 40 gage, not sure about that, but very fine
wire anyway.

This pickup isn't important (not rare/valuable), since I bought a couple
just for studying and experimentation.

Any enlightening thoughts would be appreciated. -- that's not a weather
condition or a skin treatment.

--
Cheers,
WB
..............

"Wild_Bill"

I remembered that the Z-Meter manuals specifically state that these
testers work with inductors with powdered iron/ferrite-type cores (not
steel such as power transformers), so I removed the steel screws, but the
coils still only have 4 rings.


** The pickup has a steel ( possibly Alnico ) magnet and soft iron pole
pieces, this makes for a lossy inductor - bit like a normal loudspeaker
voice coil is.

If you remove all of that, the inductance goes down and you have a low Q
inductor because of the high resistance.


... Phil

I attempted to explain that I've disassembled the humbucker pickup,
separated the 2 coils, and have removed all the metal influences from the
coils.
The magnet, pole pieces, screws, frame plate and cover have been removed and
set aside.

Just a plastic bobbin and hundreds of turns of wire.. there is no metal,
other than the coil of wire.
The desk where I'm checking the coils is wood.

At that point, there weren't even any long signal leads attached to the
coil.

So I've reassembled the pickup as originally wired, with a short pigtail of
shielded pickup coil cable.

I added an inline 1/4" jack to the pigtail, and plugged my VOX AM30 Amplug
headphone amplifier into the pigtail, and held the pickup near the guitar
strings (in the open space between the guitar's neck and bridge pickups..

and Buhh-Zinga! plenty of output from this Epiphone humbucker pickup.

This isn't a definitive performance test, but the notes sound very clear and
strong for all the strings.
I immediately plugged the H-P amp into the guitar, and the Epiphone pickup
sounded essentially the same as the guitar's DiMarzio DP155 bridge pickup.

I hadn't suspected that the Epiphone pickup was bad, but I wasn't sure since
it hadn't been installed in a guitar since I've had it.

BTW, I didn't place the metal cover back on the pickup, and I'm aware that a
metal cover will create a fairly large area for eddy current to pass, and
slightly affect the peak frequency.

I think I'll make a little gantry for suspending test pickups over the
guitar strings, for a quick bench check.

But I still don't know why the Bare coils didn't ring higher than 4 rings.
It's possible that shorted turns could exist even though the output seems to
be OK.

Oh, and forgot to mench.. the inductance measurement for the combined coils
in this pickup (when it's fully assembled) reads about 5.5 H.

--
Cheers,
WB
..............


"Phil Allison" wrote in message
...

"Wild_Bill"

I remembered that the Z-Meter manuals specifically state that these
testers work with inductors with powdered iron/ferrite-type cores (not
steel such as power transformers), so I removed the steel screws, but the
coils still only have 4 rings.


** The pickup has a steel ( possibly Alnico ) magnet and soft iron pole
pieces, this makes for a lossy inductor - bit like a normal loudspeaker
voice coil is.

If you remove all of that, the inductance goes down and you have a low Q
inductor because of the high resistance.


... Phil

On Jun 20, 2:08*am, "Wild_Bill" wrote:
I attempted to explain that I've disassembled the humbucker pickup,
separated the 2 coils, and have removed all the metal influences from the
coils.
The magnet, pole pieces, screws, frame plate and cover have been removed and
set aside.

Just a plastic bobbin and hundreds of turns of wire.. there is no metal,
other than the coil of wire.
The desk where I'm checking the coils is wood.

At that point, there weren't even any long signal leads attached to the
coil.

So I've reassembled the pickup as originally wired, with a short pigtail of
shielded pickup coil cable.

I added an inline *1/4" jack to the pigtail, and plugged my VOX AM30 Amplug
headphone amplifier into the pigtail, and held the pickup near the guitar
strings (in the open space between the guitar's neck and bridge pickups..

and Buhh-Zinga! plenty of output from this Epiphone humbucker pickup.

This isn't a definitive performance test, but the notes sound very clear and
strong for all the strings.
I immediately plugged the H-P amp into the guitar, and the Epiphone pickup
sounded essentially the same as the guitar's DiMarzio DP155 bridge pickup..

I hadn't suspected that the Epiphone pickup was bad, but I wasn't sure since
it hadn't been installed in a guitar since I've had it.

BTW, I didn't place the metal cover back on the pickup, and I'm aware that a
metal cover will create a fairly large area for eddy current to pass, and
slightly affect the peak frequency.

I think I'll make a little gantry for suspending test pickups over the
guitar strings, for a quick bench check.

But I still don't know why the Bare coils didn't ring higher than 4 rings..
It's possible that shorted turns could exist even though the output seems to
be OK.

Oh, and forgot to mench.. the inductance measurement for the combined coils
in this pickup (when it's fully assembled) reads about 5.5 H.

--
Cheers,
WB
.............

"Phil Allison" wrote in message

...





"Wild_Bill"

I remembered that the Z-Meter manuals specifically state that these
testers work with inductors with powdered iron/ferrite-type cores (not
steel such as power transformers), so I removed the steel screws, but the
coils still only have 4 rings.

** The pickup has a steel ( possibly Alnico ) magnet and soft iron pole
pieces, this makes for a lossy inductor - *bit like a normal loudspeaker
voice coil is.

If you remove all of that, the inductance goes down and you have a low Q
inductor because of the high resistance.

... *Phil- Hide quoted text -

- Show quoted text -

Because the inductance of the coil alone is VERY much smaller than the
inductance when it is placed inside the pole pieces, while the
resistance of the coil does not change. Thus the Q changes
drastically because the ratio of inductance to resistance changes
radically.

So, I've disassembled another Epiphone humbucker pickup of the same basic
type/series (but instead the neck pickup), and the Ringer Test results are
the same (4 rings whether assembled or disassembled).

Assembled pickup DC resistance 10.8k ohm, inductance 4.7H.

Disassembled pickup, coils separated from magnet, frame plate.. individual
coils inductance 2.3H

Bare coils, no screws or core plugs.. 830mH each.

--
Cheers,
WB
..............


"Wild_Bill" wrote in message
...
I know there are at least a few participants here who have guitars, so I
was wondering if anyone here has attemped a Ringer Test (inductor Q) on
guitar pickups.

"Wild_Bill"
So, I've disassembled another Epiphone humbucker pickup of the same basic
type/series (but instead the neck pickup), and the Ringer Test results are
the same (4 rings whether assembled or disassembled).

Assembled pickup DC resistance 10.8k ohm, inductance 4.7H.

Disassembled pickup, coils separated from magnet, frame plate.. individual
coils inductance 2.3H

Bare coils, no screws or core plugs.. 830mH each.


** The number is visible cycles of ringing is a guide to the Q of a resonant
circuit - the Q is approximately equal to the number of cycles.

So, your pickup coil has about a Q of 4 - either bare or assembled.

Why?

The frequency of ringing is much higher when bare.

Q = the ratio of impedance to resistance at a given frequency.



..... Phil

I'm guessing that you're unfamiliar with the Sencore Z-Meters Ringer Tests.
They're capable of indicating shorted single turns.
Fault-free inductors normally ring 10 rings or higher.

Placing a single turn of wire (with ends touching forming a conductive turn)
around an inductor will generally yield a Fail/1-thru-9 test result.

These testers work reliably for any type of inductor/transformer commonly
used in electronic equipment circuits (no core material or ferrite-type
cores, not steel core types as mentioned previously).

Guitar pickup assemblies aren't typical circuit inductors, however I kinda
expected them to Ring Test normally with the steel screws and cores removed.

--
Cheers,
WB
..............


"Phil Allison" wrote in message
...

"Wild_Bill"
So, I've disassembled another Epiphone humbucker pickup of the same basic
type/series (but instead the neck pickup), and the Ringer Test results
are the same (4 rings whether assembled or disassembled).

Assembled pickup DC resistance 10.8k ohm, inductance 4.7H.

Disassembled pickup, coils separated from magnet, frame plate..
individual coils inductance 2.3H

Bare coils, no screws or core plugs.. 830mH each.


** The number is visible cycles of ringing is a guide to the Q of a
resonant circuit - the Q is approximately equal to the number of cycles.

So, your pickup coil has about a Q of 4 - either bare or assembled.

Why?

The frequency of ringing is much higher when bare.

Q = the ratio of impedance to resistance at a given frequency.



.... Phil

"Wild_Bill"

I'm guessing that you're unfamiliar with the Sencore Z-Meters Ringer
Tests.
They're capable of indicating shorted single turns.
Fault-free inductors normally ring 10 rings or higher.

** Demonstrating that the Q is 10 or more.

As any DELIBERATE inductor will.


Placing a single turn of wire (with ends touching forming a conductive
turn) around an inductor will generally yield a Fail/1-thru-9 test result.

** Errr - cos that reduces the Q.


These testers work reliably for any type of inductor/transformer commonly
used in electronic equipment circuits (no core material or ferrite-type
cores, not steel core types as mentioned previously).

** Yep - ferrite cored and air cored deliberate inductors have high Q
factors.


Guitar pickup assemblies aren't typical circuit inductors, however I kinda
expected them to Ring Test normally with the steel screws and cores
removed.

** Show how easy it is to be wrong when making silly guesses.


..... Phil

Your fabricated Deliberate Inductor term sounds very similar to the term
Chemical Fuse.

You might be surprised/shocked to discover that many folks understand
inductors.

Use all the space you need to show how many small components exhibit over 5H
of inductance, which aren't inductors.

Would those components be Accidental or Coincidental inductors?

The Sencore Ringing Test isn't a specific measurement, it's an indication.

The inductance of an electric guitar pickup is the pickup's most significant
characteristic.

--
Cheers,
WB
..............


"Phil Allison" wrote in message
...

"Wild_Bill"

I'm guessing that you're unfamiliar with the Sencore Z-Meters Ringer
Tests.
They're capable of indicating shorted single turns.
Fault-free inductors normally ring 10 rings or higher.

** Demonstrating that the Q is 10 or more.

As any DELIBERATE inductor will.


Placing a single turn of wire (with ends touching forming a conductive
turn) around an inductor will generally yield a Fail/1-thru-9 test
result.

** Errr - cos that reduces the Q.


These testers work reliably for any type of inductor/transformer commonly
used in electronic equipment circuits (no core material or ferrite-type
cores, not steel core types as mentioned previously).

** Yep - ferrite cored and air cored deliberate inductors have high Q
factors.


Guitar pickup assemblies aren't typical circuit inductors, however I
kinda expected them to Ring Test normally with the steel screws and cores
removed.

** Show how easy it is to be wrong when making silly guesses.


.... Phil

For those who believe that the output of a guitar pickup is primarily
related to the coils' DC resistance readings, I suggest some reading would
be worthwhile.

Not from sources where the "experts" claim that the output of this model of
pickup is 13.8, when they don't even understand what the 13.8 on their ohm
meter represents.
These are often the same folks that routinely refer to the cable connector
on the guitar as the Input Jack.

The only importance of the 13.8 reading is that's the only thing their $5
DMM from Harbor Freight tells them.
Immediately they understand that a 13.8 is almost twice as hot as a 7, while
their misguided deduction realistically doesn't mean squat.

--
Cheers,
WB
..............


"Wild_Bill" wrote in message
...
I know there are at least a few participants here who have guitars, so I
was wondering if anyone here has attemped a Ringer Test (inductor Q) on
guitar pickups.

"Meat Plow Scumbag"

** I do not set up traps nor ever entrap anyone.

Lying fools and bul****ters like YOU condemn themselves in their own
words all the time.

I simply point this out occasionally.

FOAD.


Jeeze, you prove my point as by magic.


** Exposing * yourself * publicly as a fraud and a liar is no trap.

You lying pile of psychotic dung.

Get cancer and ****ing DIE.



..... Phil

On Tue, 28 Jun 2011 13:03:59 +1000, Phil Allison wrote:

"Meat Plow Scumbag"

** I do not set up traps nor ever entrap anyone.

Lying fools and bul****ters like YOU condemn themselves in their own
words all the time.

I simply point this out occasionally.

FOAD.


Jeeze, you prove my point as by magic.


** Exposing * yourself * publicly as a fraud and a liar is no trap.

You lying pile of psychotic dung.

Get cancer and ****ing DIE.

You expose anyone who disagrees with you as a "fraud".
It's time you grew up Phil. I myself have little patience
with people trying to be impostors. But I rarely show it.
Some times it's just better to bite your lip and move
on and not call people frauds, ****wits, etc...For ****'s
sake Phil if you did that with customers who always think they
know something you'd be sitting at your bench with a thumb up
your ass. I've been in the business, at a time doing warranty
work for 30 different global manufacturers so I know the business.
Sometimes I'm wrong but I don't attack people like you do. I usually
admit my wrongs gracefully and move along. I'm always in a learning
process. If you aren't and think you know everything, you are dead
wrong. I'd like to see you with a better attitude toward those that
don't have your considerable knowledge.







--
Live Fast Die Young, Leave A Pretty Corpse

"Meat Plow Criminal Scumbag"

** I do not set up traps nor ever entrap anyone.

Lying fools and bul****ters like YOU condemn themselves in their own
words all the time.

I simply point this out occasionally.

FOAD.


Jeeze, you prove my point as by magic.


** Exposing * yourself * publicly as a fraud and a liar is no trap.

You lying pile of psychotic dung.

Get cancer and ****ing DIE.

You expose anyone who disagrees with you as a "fraud".


** WRONG !!

They all, including YOU, expose themselves !!!

You lying, ****ing RABID NUT CASE

DROP ****ING DEAD



..... Phil

On Wed, 29 Jun 2011 09:24:41 +1000, Phil Allison wrote:

"Phil Allison Criminal Scumbag"

** I do not set up traps nor ever entrap anyone.

Lying fools and bul****ters like YOU condemn themselves in their
own words all the time.

I simply point this out occasionally.

FOAD.


Jeeze, you prove my point as by magic.


** Exposing * yourself * publicly as a fraud and a liar is no trap.

You lying pile of psychotic dung.

Get cancer and ****ing DIE.

You expose anyone who disagrees with you as a "fraud".


** WRONG !!

They all, including YOU, expose themselves !!!

You lying, ****ing RABID NUT CASE

DROP ****ING DEAD



.... Phil

As if by some magical spell you prove me correct in my assessment of you.




--
Live Fast Die Young, Leave A Pretty Corpse