Arcane question, and sort of long, but here goes....

Last night, young son was in the process of adding foglights to his car
and asked me for some wire to extend the harness. I wasn't sure what the
current draw would be so I grabbed one of the foglight assemblies and
connected it to the Eico 1050 battery charger/DC power supply which has
been part of my garage tool clutter for nearly 50 years:

http://home.comcast.net/~jwisnia18/temp/eico1050.jpg

When I cranked the voltage up to 13, the bulb lit brightly and the
ammeter on the Eico read around 9 amps. That seemed sort of high to me
so I asked the kid, "How big a fuse is in the harness which came with
those lights?" he looked at it and told me it was a 15 amp fuse. 15 amps
for TWO 9 amp bulbs? Obviously something was't right, so I got my
Simpson 260 and saw that the current drawn by that bulb was really a bit
less than 5 amps.

Since SWMBO was out getting some "retail therapy" I had some free time,
and taking the Eico into my workshop, I opened it up, disconnected the
leads to the ammeter and fed it with my bench supply. That verified
again that it was reading almost twice the DC current passing through it.

By a couple of "cut and trys" I found that about 4 inches of 18 gage
solid copper wire shunting the meter made it read correctly enough for
"gummint work", so I soldered that wire in and closed the Eico back up.

I believe the ammmeter is what I used to know as a "moving iron" type,
and IIRC the restoring force was supplied by some kind of permanant
magnet field, not by a mechanical spring. Am I right about that?

I doubt that Eico installed a defective meter when they built the unit
around 1965 (The date marked on the meter.) and I'm guessing that the
meter's restoring magnet weakened over 50 years, increasing its
sensitivity to nearly double.

Anyone have any similar experience with those kind of meters, I'd enjoy
learning more, just for the ****s and grins of it.

Thanks guys,

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
"Rudeness is the weak man's imitation of strength."

Jeff Wisnia wrote:

Arcane question, and sort of long, but here goes....

Last night, young son was in the process of adding foglights to his car
and asked me for some wire to extend the harness. I wasn't sure what the
current draw would be so I grabbed one of the foglight assemblies and
connected it to the Eico 1050 battery charger/DC power supply which has
been part of my garage tool clutter for nearly 50 years:

http://home.comcast.net/~jwisnia18/temp/eico1050.jpg

When I cranked the voltage up to 13, the bulb lit brightly and the
ammeter on the Eico read around 9 amps. That seemed sort of high to me
so I asked the kid, "How big a fuse is in the harness which came with
those lights?" he looked at it and told me it was a 15 amp fuse. 15 amps
for TWO 9 amp bulbs? Obviously something was't right, so I got my
Simpson 260 and saw that the current drawn by that bulb was really a bit
less than 5 amps.

Since SWMBO was out getting some "retail therapy" I had some free time,
and taking the Eico into my workshop, I opened it up, disconnected the
leads to the ammeter and fed it with my bench supply. That verified
again that it was reading almost twice the DC current passing through it.

By a couple of "cut and trys" I found that about 4 inches of 18 gage
solid copper wire shunting the meter made it read correctly enough for
"gummint work", so I soldered that wire in and closed the Eico back up.

I believe the ammmeter is what I used to know as a "moving iron" type,
and IIRC the restoring force was supplied by some kind of permanant
magnet field, not by a mechanical spring. Am I right about that?

I doubt that Eico installed a defective meter when they built the unit
around 1965 (The date marked on the meter.) and I'm guessing that the
meter's restoring magnet weakened over 50 years, increasing its
sensitivity to nearly double.

Anyone have any similar experience with those kind of meters, I'd enjoy
learning more, just for the ****s and grins of it.

Thanks guys,

Jeff


Isn't there normally a shunt across the meter movement? If so, is it
accurate? If it had changed in value that could account for the
increased reading.

Ken wrote:
Jeff Wisnia wrote:


Arcane question, and sort of long, but here goes....

Last night, young son was in the process of adding foglights to his
car and asked me for some wire to extend the harness. I wasn't sure
what the current draw would be so I grabbed one of the foglight
assemblies and connected it to the Eico 1050 battery charger/DC power
supply which has been part of my garage tool clutter for nearly 50 years:

http://home.comcast.net/~jwisnia18/temp/eico1050.jpg

When I cranked the voltage up to 13, the bulb lit brightly and the
ammeter on the Eico read around 9 amps. That seemed sort of high to me
so I asked the kid, "How big a fuse is in the harness which came with
those lights?" he looked at it and told me it was a 15 amp fuse. 15
amps for TWO 9 amp bulbs? Obviously something was't right, so I got my
Simpson 260 and saw that the current drawn by that bulb was really a
bit less than 5 amps.

Since SWMBO was out getting some "retail therapy" I had some free
time, and taking the Eico into my workshop, I opened it up,
disconnected the leads to the ammeter and fed it with my bench supply.
That verified again that it was reading almost twice the DC current
passing through it.

By a couple of "cut and trys" I found that about 4 inches of 18 gage
solid copper wire shunting the meter made it read correctly enough for
"gummint work", so I soldered that wire in and closed the Eico back up.

I believe the ammmeter is what I used to know as a "moving iron" type,
and IIRC the restoring force was supplied by some kind of permanant
magnet field, not by a mechanical spring. Am I right about that?

I doubt that Eico installed a defective meter when they built the unit
around 1965 (The date marked on the meter.) and I'm guessing that the
meter's restoring magnet weakened over 50 years, increasing its
sensitivity to nearly double.

Anyone have any similar experience with those kind of meters, I'd
enjoy learning more, just for the ****s and grins of it.

Thanks guys,

Jeff


Isn't there normally a shunt across the meter movement? If so, is
it accurate? If it had changed in value that could account for the
increased reading.


There was none across the outside, and the meter was crimped shut, so I
didn't bother looking inside.

But IIRC that kind of meter just used a few turns of heavy wire
connected across it's terminals to create a magnetic field which altered
the total dc magnetic field inside and made a piece of iron on the
pointer shaft change its position.

Jeff
--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
"Rudeness is the weak man's imitation of strength."

Jeff Wisnia wrote:
Ken wrote:
Jeff Wisnia wrote:

Arcane question, and sort of long, but here goes....

Last night, young son was in the process of adding foglights to his
car and asked me for some wire to extend the harness. I wasn't sure
what the current draw would be so I grabbed one of the foglight
assemblies and connected it to the Eico 1050 battery charger/DC power
supply which has been part of my garage tool clutter for nearly 50 years:

http://home.comcast.net/~jwisnia18/temp/eico1050.jpg

When I cranked the voltage up to 13, the bulb lit brightly and the
ammeter on the Eico read around 9 amps. That seemed sort of high to me
so I asked the kid, "How big a fuse is in the harness which came with
those lights?" he looked at it and told me it was a 15 amp fuse. 15
amps for TWO 9 amp bulbs? Obviously something was't right, so I got my
Simpson 260 and saw that the current drawn by that bulb was really a
bit less than 5 amps.

Since SWMBO was out getting some "retail therapy" I had some free
time, and taking the Eico into my workshop, I opened it up,
disconnected the leads to the ammeter and fed it with my bench supply.
That verified again that it was reading almost twice the DC current
passing through it.

By a couple of "cut and trys" I found that about 4 inches of 18 gage
solid copper wire shunting the meter made it read correctly enough for
"gummint work", so I soldered that wire in and closed the Eico back up.

I believe the ammmeter is what I used to know as a "moving iron" type,
and IIRC the restoring force was supplied by some kind of permanant
magnet field, not by a mechanical spring. Am I right about that?

I doubt that Eico installed a defective meter when they built the unit
around 1965 (The date marked on the meter.) and I'm guessing that the
meter's restoring magnet weakened over 50 years, increasing its
sensitivity to nearly double.

Anyone have any similar experience with those kind of meters, I'd
enjoy learning more, just for the ****s and grins of it.

Thanks guys,

Jeff

Isn't there normally a shunt across the meter movement? If so, is
it accurate? If it had changed in value that could account for the
increased reading.

There was none across the outside, and the meter was crimped shut, so I
didn't bother looking inside.

But IIRC that kind of meter just used a few turns of heavy wire
connected across it's terminals to create a magnetic field which altered
the total dc magnetic field inside and made a piece of iron on the
pointer shaft change its position.

Jeff

Those moving iron ones didnt usually use shunts, as you say. They were
cheap, nonlinear, undamped and inaccurate, and I expect the meter's
always been that way. It was probably a bit of marketing spin.


NT

"Jeff Wisnia" wrote in message
et...

I believe the ammmeter is what I used to know as a "moving iron" type, and
IIRC the restoring force was supplied by some kind of permanant magnet
field, not by a mechanical spring. Am I right about that?

Nope. Still a spring.

http://www.tpub.com/content/doe/h101...h1011v4_76.htm

Moving iron vane - The moving iron vane meter operates on the
principle of magnetic repulsion between like poles. The measured current
flows through a field coil which induces a like magnetic field into
a fixed and moving vane causing the moving vane to deflect a
pointer in proportion to the current or voltage applied to the coil.

"Jeff Wisnia" wrote in message
et...

Arcane question, and sort of long, but here goes....

Anyone have any similar experience with those kind of meters, I'd enjoy
learning more, just for the ****s and grins of it.

Thanks guys,

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
"Rudeness is the weak man's imitation of strength."

It's called Google and you don't play facile and excuse yourself with a poor
tag line.

DNA
"Try not to speak"

"Genome" wrote in
:


"Jeff Wisnia" wrote in message
et...

Arcane question, and sort of long, but here goes....

Anyone have any similar experience with those kind of meters, I'd
enjoy learning more, just for the ****s and grins of it.

Thanks guys,

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
"Rudeness is the weak man's imitation of strength."

It's called Google and you don't play facile and excuse yourself with
a poor tag line.

DNA
"Try not to speak"




Oops! Looks like the missing molecules spilled over again out of the blue
like they did on me some time back. On the subject of practising what we
preach, DNA might do well to speak less. Move along people, nothing to see
here. And don't get any on you!

Homer J Simpson wrote:

"Jeff Wisnia" wrote in message
et...


I believe the ammmeter is what I used to know as a "moving iron" type, and
IIRC the restoring force was supplied by some kind of permanant magnet
field, not by a mechanical spring. Am I right about that?


Nope. Still a spring.

http://www.tpub.com/content/doe/h101...h1011v4_76.htm

Moving iron vane - The moving iron vane meter operates on the
principle of magnetic repulsion between like poles. The measured current
flows through a field coil which induces a like magnetic field into
a fixed and moving vane causing the moving vane to deflect a
pointer in proportion to the current or voltage applied to the coil.



I hear what you say about a spring, and it makes sense that there may be
one there. But it's interesting that the reference link you gave
mentioned "springs" when describing the first two meter types, but not
the moving iron one. Wonder why? Probably just an oversight.

Jeff (Who is NOT going to tear that old meter on the Eico 1050 apart to
find out.)

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
"Rudeness is the weak man's imitation of strength."

"Jeff Wisnia" wrote in message
et...

I hear what you say about a spring, and it makes sense that there may be
one there. But it's interesting that the reference link you gave mentioned
"springs" when describing the first two meter types, but not the moving
iron one. Wonder why? Probably just an oversight.

Perhaps they felt it was redundant. It's like holding two magnets N to N and
S to S - you are the spring holding them together.

Jeff Wisnia wrote in
et:

Homer J Simpson wrote:

"Jeff Wisnia" wrote in message
et...


I believe the ammmeter is what I used to know as a "moving iron"
type, and IIRC the restoring force was supplied by some kind of
permanant magnet field, not by a mechanical spring. Am I right about
that?


Nope. Still a spring.

http://www.tpub.com/content/doe/h101...h1011v4_76.htm

Moving iron vane - The moving iron vane meter operates on
the principle of magnetic repulsion between like poles. The
measured current flows through a field coil which induces a like
magnetic field into a fixed and moving vane causing the
moving vane to deflect a pointer in proportion to the
current or voltage applied to the coil.



I hear what you say about a spring, and it makes sense that there may
be one there. But it's interesting that the reference link you gave
mentioned "springs" when describing the first two meter types, but not
the moving iron one. Wonder why? Probably just an oversight.

Jeff (Who is NOT going to tear that old meter on the Eico 1050 apart
to find out.)


You can test for a spring without dissection. First, does the meter jump to
a position and oscillate a bit before settling? If so, put your ear (or a
stethoscope) to the meter panel and tap it sharply. If there's a spring in
there it should ring like a bell. If you see that resonace in the meter
movement, yet hear no spring, then you and Homer are probably right, the
spring would be entirely magnetic.

The pointer itself might ring with the test I described, but dull sound,
not the sustained ring you'd likely hear from a spring designed to maintain
a pointer position.

Jeff Wisnia wrote:
Homer J Simpson wrote:

"Jeff Wisnia" wrote in message
et...


I believe the ammmeter is what I used to know as a "moving iron"
type, and IIRC the restoring force was supplied by some kind of
permanant magnet field, not by a mechanical spring. Am I right about
that?


Nope. Still a spring.

http://www.tpub.com/content/doe/h101...h1011v4_76.htm

Moving iron vane - The moving iron vane meter operates on
the principle of magnetic repulsion between like poles. The
measured current flows through a field coil which induces a like
magnetic field into a fixed and moving vane causing the moving
vane to deflect a pointer in proportion to the current or
voltage applied to the coil.



I hear what you say about a spring, and it makes sense that there may be
one there. But it's interesting that the reference link you gave
mentioned "springs" when describing the first two meter types, but not
the moving iron one. Wonder why? Probably just an oversight.

Jeff (Who is NOT going to tear that old meter on the Eico 1050 apart to
find out.)

Hit the 'Back' link at the top of the page above and you'll see the
spring.


--
Graham W http://www.gcw.org.uk/ PGM-FI page updated, Graphics Tutorial
WIMBORNE http://www.wessex-astro.org.uk/ Wessex Astro Society's Website
Dorset UK Info, Meeting Dates, Sites & Maps
Change 'news' to 'sewn' in my Reply address to avoid my spam filter.

Jeff Wisnia wrote:
Arcane question, and sort of long, but here goes....

Last night, young son was in the process of adding foglights to his car
and asked me for some wire to extend the harness. I wasn't sure what the
current draw would be so I grabbed one of the foglight assemblies and
connected it to the Eico 1050 battery charger/DC power supply which has
been part of my garage tool clutter for nearly 50 years:

http://home.comcast.net/~jwisnia18/temp/eico1050.jpg

When I cranked the voltage up to 13, the bulb lit brightly and the
ammeter on the Eico read around 9 amps. That seemed sort of high to me
so I asked the kid, "How big a fuse is in the harness which came with
those lights?" he looked at it and told me it was a 15 amp fuse. 15 amps
for TWO 9 amp bulbs? Obviously something was't right, so I got my
Simpson 260 and saw that the current drawn by that bulb was really a bit
less than 5 amps.

Since SWMBO was out getting some "retail therapy" I had some free time,
and taking the Eico into my workshop, I opened it up, disconnected the
leads to the ammeter and fed it with my bench supply. That verified
again that it was reading almost twice the DC current passing through it.

By a couple of "cut and trys" I found that about 4 inches of 18 gage
solid copper wire shunting the meter made it read correctly enough for
"gummint work", so I soldered that wire in and closed the Eico back up.

I believe the ammmeter is what I used to know as a "moving iron" type,
and IIRC the restoring force was supplied by some kind of permanant
magnet field, not by a mechanical spring. Am I right about that?

I doubt that Eico installed a defective meter when they built the unit
around 1965 (The date marked on the meter.) and I'm guessing that the
meter's restoring magnet weakened over 50 years, increasing its
sensitivity to nearly double.

Anyone have any similar experience with those kind of meters, I'd enjoy
learning more, just for the ****s and grins of it.

Could it be that the meter was calibrated to compensate for the fact
that when it's hooked to a battery, it only supplies current when the
charger exceeds the battery's voltage, while on a lamp it would draw
current from zero on up?
--
John

On 27 Sep 2006 17:16:37 -0700, "John O'Flaherty"
wrote:


Could it be that the meter was calibrated to compensate for the fact
that when it's hooked to a battery, it only supplies current when the
charger exceeds the battery's voltage, while on a lamp it would draw
current from zero on up?


No.

John

Hello John,


Could it be that the meter was calibrated to compensate for the fact
that when it's hooked to a battery, it only supplies current when the
charger exceeds the battery's voltage, while on a lamp it would draw
current from zero on up?

No.


Then maybe the meter was calibrated so it would adjust the indicated
current according to the consumer price index. Now wait, with a build
date of 1965 that doesn't computer either...

--
SCNR, Joerg

http://www.analogconsultants.com

On Wed, 27 Sep 2006 17:27:46 -0700, John Larkin
wrote:

On 27 Sep 2006 17:16:37 -0700, "John O'Flaherty"
wrote:


Could it be that the meter was calibrated to compensate for the fact
that when it's hooked to a battery, it only supplies current when the
charger exceeds the battery's voltage, while on a lamp it would draw
current from zero on up?


No.

John

Also comes to mind that if there is a magnetic pointer restraint this
is unusual, and perhaps the meter would (as usual) have bal;ance
weights to restore to zero, so perhaps it is calibrated for when the
meter face is vertical (panel mount style)? A moving iron movement
responds to RMS so waveform should not be a problem.

Peter Dettmann

Graham W wrote:


Jeff Wisnia wrote:

Homer J Simpson wrote:


"Jeff Wisnia" wrote in message
news:zLydnZVzrJEpLYfYnZ2dnUVZ_tWdnZ2d@conversen t.net...



I believe the ammmeter is what I used to know as a "moving iron"
type, and IIRC the restoring force was supplied by some kind of
permanant magnet field, not by a mechanical spring. Am I right about
that?


Nope. Still a spring.

http://www.tpub.com/content/doe/h101...h1011v4_76.htm

Moving iron vane - The moving iron vane meter operates on
the principle of magnetic repulsion between like poles. The
measured current flows through a field coil which induces a like
magnetic field into a fixed and moving vane causing the moving
vane to deflect a pointer in proportion to the current or
voltage applied to the coil.




I hear what you say about a spring, and it makes sense that there may be
one there. But it's interesting that the reference link you gave
mentioned "springs" when describing the first two meter types, but not
the moving iron one. Wonder why? Probably just an oversight.

Jeff (Who is NOT going to tear that old meter on the Eico 1050 apart to
find out.)


Hit the 'Back' link at the top of the page above and you'll see the
spring.

Got it, thanks!

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
"Rudeness is the weak man's imitation of strength."

Peter Dettmann wrote:

On Wed, 27 Sep 2006 17:27:46 -0700, John Larkin
wrote:


On 27 Sep 2006 17:16:37 -0700, "John O'Flaherty"
wrote:



Could it be that the meter was calibrated to compensate for the fact
that when it's hooked to a battery, it only supplies current when the
charger exceeds the battery's voltage, while on a lamp it would draw
current from zero on up?


No.

John


Also comes to mind that if there is a magnetic pointer restraint this
is unusual, and perhaps the meter would (as usual) have bal;ance
weights to restore to zero, so perhaps it is calibrated for when the
meter face is vertical (panel mount style)? A moving iron movement
responds to RMS so waveform should not be a problem.

Peter Dettmann

FWIW I just went down and tried an orientation test with the meter
reading 5 amps and the pointer stayed in the same position whichever way
I tipped the unit.

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
"Rudeness is the weak man's imitation of strength."

Ken wrote:

Jeff Wisnia wrote:


Arcane question, and sort of long, but here goes....

Last night, young son was in the process of adding foglights to his
car and asked me for some wire to extend the harness. I wasn't sure
what the current draw would be so I grabbed one of the foglight
assemblies and connected it to the Eico 1050 battery charger/DC power
supply which has been part of my garage tool clutter for nearly 50 years:

http://home.comcast.net/~jwisnia18/temp/eico1050.jpg

When I cranked the voltage up to 13, the bulb lit brightly and the
ammeter on the Eico read around 9 amps. That seemed sort of high to me
so I asked the kid, "How big a fuse is in the harness which came with
those lights?" he looked at it and told me it was a 15 amp fuse. 15
amps for TWO 9 amp bulbs? Obviously something was't right, so I got my
Simpson 260 and saw that the current drawn by that bulb was really a
bit less than 5 amps.

Since SWMBO was out getting some "retail therapy" I had some free
time, and taking the Eico into my workshop, I opened it up,
disconnected the leads to the ammeter and fed it with my bench supply.
That verified again that it was reading almost twice the DC current
passing through it.

By a couple of "cut and trys" I found that about 4 inches of 18 gage
solid copper wire shunting the meter made it read correctly enough for
"gummint work", so I soldered that wire in and closed the Eico back up.

I believe the ammmeter is what I used to know as a "moving iron" type,
and IIRC the restoring force was supplied by some kind of permanant
magnet field, not by a mechanical spring. Am I right about that?

I doubt that Eico installed a defective meter when they built the unit
around 1965 (The date marked on the meter.) and I'm guessing that the
meter's restoring magnet weakened over 50 years, increasing its
sensitivity to nearly double.

Anyone have any similar experience with those kind of meters, I'd
enjoy learning more, just for the ****s and grins of it.

Thanks guys,

Jeff


Isn't there normally a shunt across the meter movement? If so, is
it accurate? If it had changed in value that could account for the
increased reading.
Cheap high DC current meters were almost always iron vane and never
had a shunt.

Jeff Wisnia wrote:

Ken wrote:

Jeff Wisnia wrote:


Arcane question, and sort of long, but here goes....

Last night, young son was in the process of adding foglights to his
car and asked me for some wire to extend the harness. I wasn't sure
what the current draw would be so I grabbed one of the foglight
assemblies and connected it to the Eico 1050 battery charger/DC power
supply which has been part of my garage tool clutter for nearly 50
years:

http://home.comcast.net/~jwisnia18/temp/eico1050.jpg

When I cranked the voltage up to 13, the bulb lit brightly and the
ammeter on the Eico read around 9 amps. That seemed sort of high to
me so I asked the kid, "How big a fuse is in the harness which came
with those lights?" he looked at it and told me it was a 15 amp fuse.
15 amps for TWO 9 amp bulbs? Obviously something was't right, so I
got my Simpson 260 and saw that the current drawn by that bulb was
really a bit less than 5 amps.

Since SWMBO was out getting some "retail therapy" I had some free
time, and taking the Eico into my workshop, I opened it up,
disconnected the leads to the ammeter and fed it with my bench
supply. That verified again that it was reading almost twice the DC
current passing through it.

By a couple of "cut and trys" I found that about 4 inches of 18 gage
solid copper wire shunting the meter made it read correctly enough
for "gummint work", so I soldered that wire in and closed the Eico
back up.

I believe the ammmeter is what I used to know as a "moving iron"
type, and IIRC the restoring force was supplied by some kind of
permanant magnet field, not by a mechanical spring. Am I right about
that?

I doubt that Eico installed a defective meter when they built the
unit around 1965 (The date marked on the meter.) and I'm guessing
that the meter's restoring magnet weakened over 50 years, increasing
its sensitivity to nearly double.

Anyone have any similar experience with those kind of meters, I'd
enjoy learning more, just for the ****s and grins of it.

Thanks guys,

Jeff


Isn't there normally a shunt across the meter movement? If so, is
it accurate? If it had changed in value that could account for the
increased reading.



There was none across the outside, and the meter was crimped shut, so I
didn't bother looking inside.

But IIRC that kind of meter just used a few turns of heavy wire
connected across it's terminals to create a magnetic field which altered
the total dc magnetic field inside and made a piece of iron on the
pointer shaft change its position.

Jeff
Yep, that is the standard construction; i think a spring was used for
setting / resetting zero position.

"Jeff Wisnia" wrote in message
...
Peter Dettmann wrote:

[snip]


Also comes to mind that if there is a magnetic pointer restraint this
is unusual, and perhaps the meter would (as usual) have bal;ance
weights to restore to zero, so perhaps it is calibrated for when the
meter face is vertical (panel mount style)? A moving iron movement
responds to RMS so waveform should not be a problem.

Peter Dettmann

FWIW I just went down and tried an orientation test with the meter
reading 5 amps and the pointer stayed in the same position whichever way
I tipped the unit.


When I worked as a meter tech for EIL many years ago we calibrated iron
vane meters of various types. Most of them had a moveable metal piece that
could be adjusted to affect the calibration. Most of these meters were made
to be opened easily for repair and adjustment and scale changing, but some
(GE I think) had an aluminum band that was swaged on with a special tool to
seal the meter. All iron vane meters I worked on were for AC use, but they
might work on DC. I never tried. However, I think they relied on magnetic
induction which is an AC phenomenon, similar to a motor.

The really cheap meters were Shurite, and they used (I think) a permanent
magnet moving vane in a fixed coil. These were often DC meters used in
automotive and battery charger applications. The permanent magnet might
weaken with age, but I think that would make the meter read lower, rather
than high. If there were no magnetism, it would read zero. All meters I
worked on had springs (taut band types use the band as a spring). A weak
spring could cause a high reading.

The only meters I know to be true RMS are dynamometer types, which use a
moving coil as well as a fixed coil. When the coils are wired in series or
parallel, they read voltage or current. When the coils are separate, the
meter can be used as a wattmeter.

Of course, most such measurement is now done digitally, but it is
interesting and educational to understand the older technology. Also, many
of the lab grade meters were beautiful works of art, with varnished oak or
bakelite cases, and carefully drawn mirror scales to reduce parallax, and
to obtain accuracy to 1/4% or better.

Paul

I'm interested in this thread, having built a 1050 back in the late '50s.
It too has been part of the garage clutter for fifty years or so.

However, I am NOT willing to wade through two or three pages of quote,
quotequote, quotequotequote to get to one or two lines of answer.

PLEASE, PEOPLE, LEARN HOW TO SNIP.

Jim

RST Engineering (jw) wrote:
I'm interested in this thread, having built a 1050 back in the late '50s.
It too has been part of the garage clutter for fifty years or so.

Would you be willing to give the ammeter on your 1050 a quick check
against something you trust, either another ammeter or maybe a low
ohmage power resistor and a voltmeter and see if your unit's ammeter
reads high like mine did?


However, I am NOT willing to wade through two or three pages of quote,
quotequote, quotequotequote to get to one or two lines of answer.

PLEASE, PEOPLE, LEARN HOW TO SNIP.

Jim



I keep hearing opposing points of view about that, same as I do with
cross posting vs. duplicated separate posts.

I can see some merit to both sides of those two debates.

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
"Rudeness is the weak man's imitation of strength."

On Thu, 28 Sep 2006 13:19:26 -0400, Meat Plow wrote:
On Thu, 28 Sep 2006 10:11:06 -0700, RST Engineering (jw) Has Frothed:

I'm interested in this thread, having built a 1050 back in the late '50s.
It too has been part of the garage clutter for fifty years or so.

However, I am NOT willing to wade through two or three pages of quote,
quotequote, quotequotequote to get to one or two lines of answer.

PLEASE, PEOPLE, LEARN HOW TO SNIP.

Use a news reader that can mute quoted text.

Screw you. Post right - don't make other people compensate for your own
shortcomings.

Thanks,
Rich

Meat Plow wrote:
On Thu, 28 Sep 2006 18:51:06 +0000, Rich Grise Has Frothed:
On Thu, 28 Sep 2006 13:19:26 -0400, Meat Plow wrote:
On Thu, 28 Sep 2006 10:11:06 -0700, RST Engineering (jw) Has Frothed:

I'm interested in this thread, having built a 1050 back in the late
'50s. It too has been part of the garage clutter for fifty years or so.

However, I am NOT willing to wade through two or three pages of quote,
quotequote, quotequotequote to get to one or two lines of answer.

PLEASE, PEOPLE, LEARN HOW TO SNIP.

Use a news reader that can mute quoted text.

Screw you. Post right - don't make other people compensate for your own
shortcomings.

Show RFC where quoting is a shortcoming. It's up to the individual to skip
over or mute quoted content.

*plonk*


Tim

"Meat Plow" wrote in message
news
Show RFC where quoting is a shortcoming. It's up to the individual to skip
over or mute quoted content.

Consider the blind - who listen to Usenet. They have to wade through a
mountain of crap to hear one line - or sometimes none.

In article Z_ZSg.4671$N4.1899@clgrps12,
Homer J Simpson wrote:

"Meat Plow" wrote in message
news
Show RFC where quoting is a shortcoming. It's up to the individual to skip
over or mute quoted content.

Consider the blind - who listen to Usenet. They have to wade through a
mountain of crap to hear one line - or sometimes none.

RFC 1855, "Netiquette Guidelines",

Section 3: One-to-many communication (mailing lists, netnews),

3.1 User guidelines

3.1.1 General Guidelines for mailing lists and NetNews

[bullet 10]: If you are sending a reply to a message or a
posting be sure you summarize the original at the top of the
message, or include just enough text of the original to give a
context. This will make sure readers understand when they start
to read your response. Since NetNews, especially, is
proliferated by distributing the postings from one host to
another, it is possible to see a response to a message before
seeing the original. Giving context helps everyone. But do not
include the entire original!

I take this as saying that quoting, when used in moderation to carry
forward the essential context of a thread, is Good, and that when used
to excess (quoting the entire original, or the whole thread), is Bad.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

On Fri, 29 Sep 2006 00:30:31 +0100, Tim Auton did the cha-cha, and
screamed:
Meat Plow wrote:
On Thu, 28 Sep 2006 18:51:06 +0000, Rich Grise Has Frothed:
On Thu, 28 Sep 2006 13:19:26 -0400, Meat Plow wrote:
On Thu, 28 Sep 2006 10:11:06 -0700, RST Engineering (jw) Has Frothed:

I'm interested in this thread, having built a 1050 back in the late
'50s. It too has been part of the garage clutter for fifty years or
so.

However, I am NOT willing to wade through two or three pages of
quote, quotequote, quotequotequote to get to one or two lines of
answer.

PLEASE, PEOPLE, LEARN HOW TO SNIP.

Use a news reader that can mute quoted text.

Screw you. Post right - don't make other people compensate for your own
shortcomings.

Show RFC where quoting is a shortcoming. It's up to the individual to
skip over or mute quoted content.

*plonk*

Give my regards to the Nestene Consciousness.

--
__________________________________________________ ______________________
Hail Eris! TM#5; COOSN-029-06-71069
Cardinal Snarky of the Fannish Inquisition
http://www6.kingdomofloathing.com/login.php
http://www.runescape.com/
No one expects the Fannish Inquisition!
http://groups.yahoo.com/group/Cabal_...y_Pretzel/join
"Etymology:
Argumentum ad Septicus : argument to putrefaction. Derived from Septicum
Argumentum : putrefaction of argument.

"Septic \Sep"tic\, Septical \Sep"tic*al\
a. [L. septicus to make putrid: cf. F. septique.]
Having power to promote putrefaction. Of or relating to or
caused by putrefaction." -- Kadaitcha Man, indirectly to
Donald "Skeptic"/"Septic" Alford, in MID:

"I never fail to be amazing" -- Looney Maroon for September 2006 nominee
William Barwell's ego knows no bounds. MID:


"We are most nearly ourselves when we achieve the seriousness of the
child at play." -- Heraclitus

"And thats another mistake on your part. Your 'playing' games on usenet,
and I'm not playing...It has nothing to do with impressing you, it has
more to do with making sure you have the education you'll need to debate.
The debate is no fun for me if you are mentally incapable of it. I'm
giving you an opportunity to educate yourself. That's all." -- A trashy
former virus-writer turned Outer Filth doesn't know if he's playing or
working, in MID: om

On Fri, 29 Sep 2006 00:43:37 +0000, Homer J Simpson did the cha-cha, and
screamed:
"Meat Plow" wrote...

Show RFC where quoting is a shortcoming. It's up to the individual to
skip over or mute quoted content.

Consider the blind - who listen to Usenet. They have to wade through a
mountain of crap to hear one line - or sometimes none.

Consider your killfile.

--
__________________________________________________ ______________________
Hail Eris! TM#5; COOSN-029-06-71069
Cardinal Snarky of the Fannish Inquisition
http://www6.kingdomofloathing.com/login.php
http://www.runescape.com/
No one expects the Fannish Inquisition!
http://groups.yahoo.com/group/Cabal_...y_Pretzel/join
"Etymology:
Argumentum ad Septicus : argument to putrefaction. Derived from Septicum
Argumentum : putrefaction of argument.

"Septic \Sep"tic\, Septical \Sep"tic*al\
a. [L. septicus to make putrid: cf. F. septique.]
Having power to promote putrefaction. Of or relating to or
caused by putrefaction." -- Kadaitcha Man, indirectly to
Donald "Skeptic"/"Septic" Alford, in MID:

"I never fail to be amazing" -- Looney Maroon for September 2006 nominee
William Barwell's ego knows no bounds. MID:


"We are most nearly ourselves when we achieve the seriousness of the
child at play." -- Heraclitus

"And thats another mistake on your part. Your 'playing' games on usenet,
and I'm not playing...It has nothing to do with impressing you, it has
more to do with making sure you have the education you'll need to debate.
The debate is no fun for me if you are mentally incapable of it. I'm
giving you an opportunity to educate yourself. That's all." -- A trashy
former virus-writer turned Outer Filth doesn't know if he's playing or
working, in MID: om

"The Demon Prince of Absurdity" wrote in
message news
Consider your killfile.

If I kill-filed everyone who was too clueless to post correctly it would be
a lonely place.

On Fri, 29 Sep 2006 04:23:07 +0000, Homer J Simpson attempted to confuse
the issue further by squeaking:
"The Demon Prince of Absurdity" wrote...

Consider your killfile.

If I kill-filed everyone who was too clueless to post correctly it would
be a lonely place.

Well, you could always try realising that usenet's meant for laughs.
"Serious discussion" is a waste of bandwidth.;-{P}

--
__________________________________________________ ______________________
Hail Eris! mhm 29x21; TM#5; COOSN-029-06-71069
The God of Odd Statements, the Ugliest Pig****er In The Universe
Stupidity Takes Its Toll. Please Have Exact Change.
Thread where outing begins: http://tinyurl.com/hojf8
George Pickett Memorial Trophy, Special Ops Cody Memorial Purple Heart,
and the Order of the Holey Sockpuppet winner on
outing personal contact info in x-poasted subject lines:
"Plenty of people post under their real names and do not attempt to hide
their contact info. You are scared of being 'outed' because you are a
pathological abuser of usenet, and people rightly despise you for it.
You're afraid of being reported to the authorities or, better, visited
by a couple of guys with baseball bats. Other people don't have this
obsessive fear. Ward Hardman himself has posted plenty of personal
information - nothing that anyone else added was hidden in any way.
You're so ****ing scared you've built up this whole sick mythology about
different categories of bad dudes who 'out' scum like you.

"Meanwhile you are the ugliest pig****er in the universe. You are the
coward without ethics. You call me a 'newbie' - ha! what an asshole you
are. Those who want to remain anonymous do so. There is absolutely no
way you could identify me, not unless you had the sort of subpoena power
that only gets turned on for big-time terrorists. That's because I chose
to be anonymous. Some people don't. Only really stupid dicks like you
choose the sort of semi-anonymity which leaves you in constant fear.

"What a dickless wonder you are 'Snarky' you fat asshole."
-- in MID: . com

The Demon Prince of Absurdity wrote in
news
Give my regards to the Nestene Consciousness.


Likewise.

On Fri, 29 Sep 2006 00:43:37 GMT, "Homer J Simpson"
wrote:


"Meat Plow" wrote in message
news
Show RFC where quoting is a shortcoming. It's up to the individual to skip
over or mute quoted content.

Consider the blind - who listen to Usenet. They have to wade through a
mountain of crap to hear one line - or sometimes none.

---
So we should all carry white canes?


--
John Fields
Professional Circuit Designer

wrote:
Jeff Wisnia wrote:


Since SWMBO was out getting some "retail therapy" I had some free
time, and taking the Eico into my workshop, I opened it up,
disconnected the leads to the ammeter and fed it with my bench supply.
That verified again that it was reading almost twice the DC current
passing through it.

if you want it to read right, remove a turn or 2 on the coil. Not sure
if I'd bother though.

NT

"Meat Plow" wrote in message
news
If I kill-filed everyone who was too clueless to post correctly it would
be a lonely place.

Pretty good reason then not to **** and moan about it right?

But it's still worth reminding folk to snip. Try being on a mail list where
someone replies to a 50 message digest - and adds nothing to the glop.

"John Fields" wrote in message
...

Consider the blind - who listen to Usenet. They have to wade through a
mountain of crap to hear one line - or sometimes none.

So we should all carry white canes?

You're an American. I don't expect you to give a damn about your fellow
citizens - or anyone else on earth.

Homer J Simpson wrote:
"John Fields" wrote in message
...

Consider the blind - who listen to Usenet. They have to wade
through a mountain of crap to hear one line - or sometimes none.

So we should all carry white canes?

You're an American. I don't expect you to give a damn about your
fellow citizens - or anyone else on earth.

Jealousy like that is so ugly.

"Damian" wrote in message
reenews.net...

Consider the blind - who listen to Usenet. They have to wade
through a mountain of crap to hear one line - or sometimes none.

So we should all carry white canes?

You're an American. I don't expect you to give a damn about your
fellow citizens - or anyone else on earth.

Jealousy like that is so ugly.

Who the hell is jealous of you? I merely write what I observe.

Homer J Simpson wrote:
"Damian" wrote in message
reenews.net...

Consider the blind - who listen to Usenet. They have to wade
through a mountain of crap to hear one line - or sometimes none.

So we should all carry white canes?

You're an American. I don't expect you to give a damn about your
fellow citizens - or anyone else on earth.

Jealousy like that is so ugly.

Who the hell is jealous of you?

I don't know, why do you ask? Are you jealous of more than John?

I merely write what I observe.

Oh, you're vision impaired. Sorry.

"Damian" wrote in message
reenews.net...

Jealousy like that is so ugly.

Who the hell is jealous of you?

I don't know, why do you ask? Are you jealous of more than John?

I merely write what I observe.

Oh, you're vision impaired. Sorry.

Better than being brain impaired like you.