reduce 125VAC to 120VAC, small form factor, and clean 60Hz s

[John Fields]

On Fri, 12 Apr 2013 18:39:48 -0700, John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Fri, 12 Apr 2013 01:31:53 -0400, "P E Schoen" <paul@peschoen.com> wrote:

"John Larkin" wrote in message
news:s86em81bhs0q8glvlh9mnh0skad6its081@4ax.com...

On Thu, 11 Apr 2013 14:34:21 -0500, John Fields
jfields@austininstruments.com> wrote:

Because "Failure mode" is a bit too harsh, I think, since they're
designed to take a lot of abuse.

However, if you want to play specmanship, we might talk about the
increase of turn-to-turn leakage reactance with respect to frequency,
and the leakage from winding to core.

What in the world could all that word salad blather possibly mean?

What, specifically, is a Variac going to do as the frequency is
increased from 60 Hz to 1 KHz?

This is getting rather silly, and JF seems to be grasping at straws.

---
I just want to see some real test data.
---

Toroids are often used for high quality audio and high efficiency
power transformers because they have much less leakage inductance
than EI and other core types. Here is some information on toroidal
power transformers where the corner frequency is about 50 kHz:
http://www.toruspower.com/nbt-narrow-bandwidth-technology/

---
Fixed "n" toroidal high quality audio and power transformers aren't
the same animals as variable "n" variacs, so equating one to the other
is a little risky, I think.
---

Even if the laminations in a variac are optimized for cost at 60 Hz, core losses
will still be moderate at, say, 1 KHz. The OP was concerned with 60 Hz plus
harmonics, so in that case the HF component would be small, so core loss is not
an issue at all.

---
You posted earlier that the bandwidth of the variac would be high
enough to pass the harmonics, and now you post that the harmonic
content will be small, without even having a clue as to the output
waveform of the variac.

Why don't you just test your variac and put the whole thing to rest?
---

At high line frequencies, leakage inductance will soften up the load regulation
a bit, but toroids have very low leakage inductance. With the Variac in/out
ratio anywhere near 1.0, inductive effects are still smaller.

Yes, JF is flailing, tossing around words as if he understands what they mean.

---
Whatever you say, John.
---

Even the lowest corner frequency was 3 kHz, but this was in the context of a
low pass filter where it was desired to attenuate higher frequency
components of power line noise. But it seems evident that these toroids work
well at high audio frequencies.

---
If it seems evident that those toroids work well at high audio
frequencies, consideration should be given to the fact that they
aren't variacs, and that they do so by design.
---

My own measurements were supposed to
determine if a given core size for 60 Hz could be used at higher frequencies
and correspondingly higher voltage and power levels.

The results indicate that there will be higher core loss at higher frequency
which may be proportional to the square root of frequency, so if my toroid
has 0.5% core loss at 60 Hz it may have 1% at 240 Hz and 2% at 1 kHz and 4%
at 4 kHz. But that is also accompanied by total power capacity increase from
80 VA at 60 Hz to 1.3 kVA at 1 KHz. Thus there may be 26W of core loss, but
that may be acceptable if the smaller size is a major advantage.

---
But that's for transformers that aren't variacs.

Tell ya what I'm going to do: I'll go ahead and test my variac and
post what I find, regardless of what "Mr. Perfect" does.
---

Here is another link that may be helpful (although JF may never accept that
he is wrong):
http://www.ipst.org/TechPapers/2003/IPST03Paper9c-3.pdf

This is specifically for medium voltage (600V-5kV) conventional current
transformers (which are usually silicon steel tape wound toroids), and it
shows good linearity and phase shift up to at least 50 kHz, which is vital
for transient response in electronic protection systems.

---
Since a variac is not a conventional current transformer, prove me
wrong with relevant data.
---

According to the following information, standard Talema toroidal
transformers are rated only to 450 Hz, but with other core materials
frequencies up to 100kHz are possible.

---
If frogs had wings...
---

Tape wound cores with high nickel content allow higher frequencies.

http://www.talema.net/en/products/pdf/Trafo%20Catalog%20-%20English%20Feb-08.pdf

---
OK, but why is that germane?
---

Here is an interesting article on the "Variac":
http://sound.westhost.com/articles/variac.htm

Paul

Nice, but I don't understand the line...

"Care is needed to ensure that the variac's current rating is not exceeded at
low brightness settings, where filament resistance is much lower than normal."

---
I think that's an error.

From abse:

news:7kbim858vdbgefe2031qhbs409ui4nv416@4ax.com

--
JF

 

[John Larkin]

On Sat, 13 Apr 2013 05:49:50 -0500, John Fields <jfields@austininstruments.com>
wrote:

On Fri, 12 Apr 2013 18:39:48 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Fri, 12 Apr 2013 01:31:53 -0400, "P E Schoen" <paul@peschoen.com> wrote:

"John Larkin" wrote in message
news:s86em81bhs0q8glvlh9mnh0skad6its081@4ax.com...

On Thu, 11 Apr 2013 14:34:21 -0500, John Fields
jfields@austininstruments.com> wrote:

Because "Failure mode" is a bit too harsh, I think, since they're
designed to take a lot of abuse.

However, if you want to play specmanship, we might talk about the
increase of turn-to-turn leakage reactance with respect to frequency,
and the leakage from winding to core.

What in the world could all that word salad blather possibly mean?

What, specifically, is a Variac going to do as the frequency is
increased from 60 Hz to 1 KHz?

This is getting rather silly, and JF seems to be grasping at straws.

---
I just want to see some real test data.

You claim to have all te necessary gear. If you e=want to see test data, why
don't you do it yourself? If I did measure a Variac up into the KHz, you'd most
likely not like the results and accuse me of faking the data.

Silly, useless old fart.

---

Toroids are often used for high quality audio and high efficiency
power transformers because they have much less leakage inductance
than EI and other core types. Here is some information on toroidal
power transformers where the corner frequency is about 50 kHz:
http://www.toruspower.com/nbt-narrow-bandwidth-technology/

---
Fixed "n" toroidal high quality audio and power transformers aren't
the same animals as variable "n" variacs, so equating one to the other
is a little risky, I think.
---

Even if the laminations in a variac are optimized for cost at 60 Hz, core losses
will still be moderate at, say, 1 KHz. The OP was concerned with 60 Hz plus
harmonics, so in that case the HF component would be small, so core loss is not
an issue at all.

---
You posted earlier that the bandwidth of the variac would be high
enough to pass the harmonics, and now you post that the harmonic
content will be small, without even having a clue as to the output
waveform of the variac.

Why don't you just test your variac and put the whole thing to rest?
---

At high line frequencies, leakage inductance will soften up the load regulation
a bit, but toroids have very low leakage inductance. With the Variac in/out
ratio anywhere near 1.0, inductive effects are still smaller.

Yes, JF is flailing, tossing around words as if he understands what they mean.

---
Whatever you say, John.
---

Even the lowest corner frequency was 3 kHz, but this was in the context of a
low pass filter where it was desired to attenuate higher frequency
components of power line noise. But it seems evident that these toroids work
well at high audio frequencies.

---
If it seems evident that those toroids work well at high audio
frequencies, consideration should be given to the fact that they
aren't variacs, and that they do so by design.
---

My own measurements were supposed to
determine if a given core size for 60 Hz could be used at higher frequencies
and correspondingly higher voltage and power levels.

The results indicate that there will be higher core loss at higher frequency
which may be proportional to the square root of frequency, so if my toroid
has 0.5% core loss at 60 Hz it may have 1% at 240 Hz and 2% at 1 kHz and 4%
at 4 kHz. But that is also accompanied by total power capacity increase from
80 VA at 60 Hz to 1.3 kVA at 1 KHz. Thus there may be 26W of core loss, but
that may be acceptable if the smaller size is a major advantage.

---
But that's for transformers that aren't variacs.

Tell ya what I'm going to do: I'll go ahead and test my variac and
post what I find, regardless of what "Mr. Perfect" does.

Can't wait.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

 

[Jamie]

John Larkin wrote:

On Sat, 13 Apr 2013 05:49:50 -0500, John Fields <jfields@austininstruments.com
wrote:


On Fri, 12 Apr 2013 18:39:48 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:


On Fri, 12 Apr 2013 01:31:53 -0400, "P E Schoen" <paul@peschoen.com> wrote:


"John Larkin" wrote in message
news:s86em81bhs0q8glvlh9mnh0skad6its081@4ax.com...


On Thu, 11 Apr 2013 14:34:21 -0500, John Fields
jfields@austininstruments.com> wrote:

Because "Failure mode" is a bit too harsh, I think, since they're
designed to take a lot of abuse.

However, if you want to play specmanship, we might talk about the
increase of turn-to-turn leakage reactance with respect to frequency,
and the leakage from winding to core.

What in the world could all that word salad blather possibly mean?

What, specifically, is a Variac going to do as the frequency is
increased from 60 Hz to 1 KHz?

This is getting rather silly, and JF seems to be grasping at straws.

---
I just want to see some real test data.


You claim to have all te necessary gear. If you e=want to see test data, why
don't you do it yourself? If I did measure a Variac up into the KHz, you'd most
likely not like the results and accuse me of faking the data.

Silly, useless old fart.





---


Toroids are often used for high quality audio and high efficiency
power transformers because they have much less leakage inductance
than EI and other core types. Here is some information on toroidal
power transformers where the corner frequency is about 50 kHz:
http://www.toruspower.com/nbt-narrow-bandwidth-technology/

---
Fixed "n" toroidal high quality audio and power transformers aren't
the same animals as variable "n" variacs, so equating one to the other
is a little risky, I think.
---


Even if the laminations in a variac are optimized for cost at 60 Hz, core losses
will still be moderate at, say, 1 KHz. The OP was concerned with 60 Hz plus
harmonics, so in that case the HF component would be small, so core loss is not
an issue at all.

---
You posted earlier that the bandwidth of the variac would be high
enough to pass the harmonics, and now you post that the harmonic
content will be small, without even having a clue as to the output
waveform of the variac.

Why don't you just test your variac and put the whole thing to rest?
---


At high line frequencies, leakage inductance will soften up the load regulation
a bit, but toroids have very low leakage inductance. With the Variac in/out
ratio anywhere near 1.0, inductive effects are still smaller.

Yes, JF is flailing, tossing around words as if he understands what they mean.

---
Whatever you say, John.
---


Even the lowest corner frequency was 3 kHz, but this was in the context of a
low pass filter where it was desired to attenuate higher frequency
components of power line noise. But it seems evident that these toroids work
well at high audio frequencies.

---
If it seems evident that those toroids work well at high audio
frequencies, consideration should be given to the fact that they
aren't variacs, and that they do so by design.
---


My own measurements were supposed to
determine if a given core size for 60 Hz could be used at higher frequencies
and correspondingly higher voltage and power levels.

The results indicate that there will be higher core loss at higher frequency
which may be proportional to the square root of frequency, so if my toroid
has 0.5% core loss at 60 Hz it may have 1% at 240 Hz and 2% at 1 kHz and 4%
at 4 kHz. But that is also accompanied by total power capacity increase from
80 VA at 60 Hz to 1.3 kVA at 1 KHz. Thus there may be 26W of core loss, but
that may be acceptable if the smaller size is a major advantage.

---
But that's for transformers that aren't variacs.

Tell ya what I'm going to do: I'll go ahead and test my variac and
post what I find, regardless of what "Mr. Perfect" does.


Can't wait.


Film at 11:00

Jamie

 

[Michael A. Terrell]

Jamie wrote:

Film at 11:00

Don't sell yourself short, slime.

 

[John Larkin]

On Sat, 13 Apr 2013 13:17:16 -0400, Jamie
<jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:

John Larkin wrote:

On Sat, 13 Apr 2013 05:49:50 -0500, John Fields <jfields@austininstruments.com
wrote:


On Fri, 12 Apr 2013 18:39:48 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:


On Fri, 12 Apr 2013 01:31:53 -0400, "P E Schoen" <paul@peschoen.com> wrote:


"John Larkin" wrote in message
news:s86em81bhs0q8glvlh9mnh0skad6its081@4ax.com...


On Thu, 11 Apr 2013 14:34:21 -0500, John Fields
jfields@austininstruments.com> wrote:

Because "Failure mode" is a bit too harsh, I think, since they're
designed to take a lot of abuse.

However, if you want to play specmanship, we might talk about the
increase of turn-to-turn leakage reactance with respect to frequency,
and the leakage from winding to core.

What in the world could all that word salad blather possibly mean?

What, specifically, is a Variac going to do as the frequency is
increased from 60 Hz to 1 KHz?

This is getting rather silly, and JF seems to be grasping at straws.

---
I just want to see some real test data.


You claim to have all te necessary gear. If you e=want to see test data, why
don't you do it yourself? If I did measure a Variac up into the KHz, you'd most
likely not like the results and accuse me of faking the data.

Silly, useless old fart.





---


Toroids are often used for high quality audio and high efficiency
power transformers because they have much less leakage inductance
than EI and other core types. Here is some information on toroidal
power transformers where the corner frequency is about 50 kHz:
http://www.toruspower.com/nbt-narrow-bandwidth-technology/

---
Fixed "n" toroidal high quality audio and power transformers aren't
the same animals as variable "n" variacs, so equating one to the other
is a little risky, I think.
---


Even if the laminations in a variac are optimized for cost at 60 Hz, core losses
will still be moderate at, say, 1 KHz. The OP was concerned with 60 Hz plus
harmonics, so in that case the HF component would be small, so core loss is not
an issue at all.

---
You posted earlier that the bandwidth of the variac would be high
enough to pass the harmonics, and now you post that the harmonic
content will be small, without even having a clue as to the output
waveform of the variac.

Why don't you just test your variac and put the whole thing to rest?
---


At high line frequencies, leakage inductance will soften up the load regulation
a bit, but toroids have very low leakage inductance. With the Variac in/out
ratio anywhere near 1.0, inductive effects are still smaller.

Yes, JF is flailing, tossing around words as if he understands what they mean.

---
Whatever you say, John.
---


Even the lowest corner frequency was 3 kHz, but this was in the context of a
low pass filter where it was desired to attenuate higher frequency
components of power line noise. But it seems evident that these toroids work
well at high audio frequencies.

---
If it seems evident that those toroids work well at high audio
frequencies, consideration should be given to the fact that they
aren't variacs, and that they do so by design.
---


My own measurements were supposed to
determine if a given core size for 60 Hz could be used at higher frequencies
and correspondingly higher voltage and power levels.

The results indicate that there will be higher core loss at higher frequency
which may be proportional to the square root of frequency, so if my toroid
has 0.5% core loss at 60 Hz it may have 1% at 240 Hz and 2% at 1 kHz and 4%
at 4 kHz. But that is also accompanied by total power capacity increase from
80 VA at 60 Hz to 1.3 kVA at 1 KHz. Thus there may be 26W of core loss, but
that may be acceptable if the smaller size is a major advantage.

---
But that's for transformers that aren't variacs.

Tell ya what I'm going to do: I'll go ahead and test my variac and
post what I find, regardless of what "Mr. Perfect" does.


Can't wait.


Film at 11:00

Jamie

He won't actually do it. And if he did, the stuff he measures won't make sense.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

 

[John Fields]

On Sat, 13 Apr 2013 08:57:04 -0700, John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Sat, 13 Apr 2013 05:49:50 -0500, John Fields <jfields@austininstruments.com
wrote:

On Fri, 12 Apr 2013 18:39:48 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Fri, 12 Apr 2013 01:31:53 -0400, "P E Schoen" <paul@peschoen.com> wrote:

"John Larkin" wrote in message
news:s86em81bhs0q8glvlh9mnh0skad6its081@4ax.com...

On Thu, 11 Apr 2013 14:34:21 -0500, John Fields
jfields@austininstruments.com> wrote:

Because "Failure mode" is a bit too harsh, I think, since they're
designed to take a lot of abuse.

However, if you want to play specmanship, we might talk about the
increase of turn-to-turn leakage reactance with respect to frequency,
and the leakage from winding to core.

What in the world could all that word salad blather possibly mean?

What, specifically, is a Variac going to do as the frequency is
increased from 60 Hz to 1 KHz?

This is getting rather silly, and JF seems to be grasping at straws.

---
I just want to see some real test data.

You claim to have all te necessary gear. If you e=want to see test data, why
don't you do it yourself? If I did measure a Variac up into the KHz, you'd most
likely not like the results and accuse me of faking the data.

---
Not at all.

What I object to is your making claims which you refuse to back up
with real-world data which can be replicated.

Sort of like Joseph Newman, who's from your neck of the woods as I
understand it.

Then there's the matter of you apparently ignoring my request for your
variac's manufacturer and model/part number.

Why would you do that?
---

Silly, useless old fart.

---
Wow, the anal references which you earlier found repugnant now seem to
emanating from your camp.
---

Toroids are often used for high quality audio and high efficiency
power transformers because they have much less leakage inductance
than EI and other core types. Here is some information on toroidal
power transformers where the corner frequency is about 50 kHz:
http://www.toruspower.com/nbt-narrow-bandwidth-technology/

---
Fixed "n" toroidal high quality audio and power transformers aren't
the same animals as variable "n" variacs, so equating one to the other
is a little risky, I think.
---

Even if the laminations in a variac are optimized for cost at 60 Hz, core losses
will still be moderate at, say, 1 KHz. The OP was concerned with 60 Hz plus
harmonics, so in that case the HF component would be small, so core loss is not
an issue at all.

---
You posted earlier that the bandwidth of the variac would be high
enough to pass the harmonics, and now you post that the harmonic
content will be small, without even having a clue as to the output
waveform of the variac.

Why don't you just test your variac and put the whole thing to rest?
---

At high line frequencies, leakage inductance will soften up the load regulation
a bit, but toroids have very low leakage inductance. With the Variac in/out
ratio anywhere near 1.0, inductive effects are still smaller.

Yes, JF is flailing, tossing around words as if he understands what they mean.

---
Whatever you say, John.
---

Even the lowest corner frequency was 3 kHz, but this was in the context of a
low pass filter where it was desired to attenuate higher frequency
components of power line noise. But it seems evident that these toroids work
well at high audio frequencies.

---
If it seems evident that those toroids work well at high audio
frequencies, consideration should be given to the fact that they
aren't variacs, and that they do so by design.
---

My own measurements were supposed to
determine if a given core size for 60 Hz could be used at higher frequencies
and correspondingly higher voltage and power levels.

The results indicate that there will be higher core loss at higher frequency
which may be proportional to the square root of frequency, so if my toroid
has 0.5% core loss at 60 Hz it may have 1% at 240 Hz and 2% at 1 kHz and 4%
at 4 kHz. But that is also accompanied by total power capacity increase from
80 VA at 60 Hz to 1.3 kVA at 1 KHz. Thus there may be 26W of core loss, but
that may be acceptable if the smaller size is a major advantage.

---
But that's for transformers that aren't variacs.

Tell ya what I'm going to do: I'll go ahead and test my variac and
post what I find, regardless of what "Mr. Perfect" does.

Can't wait.

---
But, poor baby, you'll have to.

--
JF

 

[John Fields]

On Sat, 13 Apr 2013 11:41:28 -0700, John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

He won't actually do it. And if he did, the stuff he measures won't make sense.

---
To you, perhaps, since it may be at odds with what you want to hear,
but I'm intrigued...

Why don't you run your own tests and present them as prima facie
evidence to support your position instead of threatening to shoot down
everyone else's positions as being untenable?

--
JF

 

[John Larkin]

On Sat, 13 Apr 2013 14:00:19 -0500, John Fields <jfields@austininstruments.com>
wrote:

On Sat, 13 Apr 2013 08:57:04 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Sat, 13 Apr 2013 05:49:50 -0500, John Fields <jfields@austininstruments.com
wrote:

On Fri, 12 Apr 2013 18:39:48 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Fri, 12 Apr 2013 01:31:53 -0400, "P E Schoen" <paul@peschoen.com> wrote:

"John Larkin" wrote in message
news:s86em81bhs0q8glvlh9mnh0skad6its081@4ax.com...

On Thu, 11 Apr 2013 14:34:21 -0500, John Fields
jfields@austininstruments.com> wrote:

Because "Failure mode" is a bit too harsh, I think, since they're
designed to take a lot of abuse.

However, if you want to play specmanship, we might talk about the
increase of turn-to-turn leakage reactance with respect to frequency,
and the leakage from winding to core.

What in the world could all that word salad blather possibly mean?

What, specifically, is a Variac going to do as the frequency is
increased from 60 Hz to 1 KHz?

This is getting rather silly, and JF seems to be grasping at straws.

---
I just want to see some real test data.

You claim to have all te necessary gear. If you e=want to see test data, why
don't you do it yourself? If I did measure a Variac up into the KHz, you'd most
likely not like the results and accuse me of faking the data.

---
Not at all.

What I object to is your making claims which you refuse to back up
with real-world data which can be replicated.

Sort of like Joseph Newman, who's from your neck of the woods as I
understand it.

Then there's the matter of you apparently ignoring my request for your
variac's manufacturer and model/part number.

Why would you do that?
---

Silly, useless old fart.

---
Wow, the anal references which you earlier found repugnant now seem to
emanating from your camp.
---

Toroids are often used for high quality audio and high efficiency
power transformers because they have much less leakage inductance
than EI and other core types. Here is some information on toroidal
power transformers where the corner frequency is about 50 kHz:
http://www.toruspower.com/nbt-narrow-bandwidth-technology/

---
Fixed "n" toroidal high quality audio and power transformers aren't
the same animals as variable "n" variacs, so equating one to the other
is a little risky, I think.
---

Even if the laminations in a variac are optimized for cost at 60 Hz, core losses
will still be moderate at, say, 1 KHz. The OP was concerned with 60 Hz plus
harmonics, so in that case the HF component would be small, so core loss is not
an issue at all.

---
You posted earlier that the bandwidth of the variac would be high
enough to pass the harmonics, and now you post that the harmonic
content will be small, without even having a clue as to the output
waveform of the variac.

Why don't you just test your variac and put the whole thing to rest?
---

At high line frequencies, leakage inductance will soften up the load regulation
a bit, but toroids have very low leakage inductance. With the Variac in/out
ratio anywhere near 1.0, inductive effects are still smaller.

Yes, JF is flailing, tossing around words as if he understands what they mean.

---
Whatever you say, John.
---

Even the lowest corner frequency was 3 kHz, but this was in the context of a
low pass filter where it was desired to attenuate higher frequency
components of power line noise. But it seems evident that these toroids work
well at high audio frequencies.

---
If it seems evident that those toroids work well at high audio
frequencies, consideration should be given to the fact that they
aren't variacs, and that they do so by design.
---

My own measurements were supposed to
determine if a given core size for 60 Hz could be used at higher frequencies
and correspondingly higher voltage and power levels.

The results indicate that there will be higher core loss at higher frequency
which may be proportional to the square root of frequency, so if my toroid
has 0.5% core loss at 60 Hz it may have 1% at 240 Hz and 2% at 1 kHz and 4%
at 4 kHz. But that is also accompanied by total power capacity increase from
80 VA at 60 Hz to 1.3 kVA at 1 KHz. Thus there may be 26W of core loss, but
that may be acceptable if the smaller size is a major advantage.

---
But that's for transformers that aren't variacs.

Tell ya what I'm going to do: I'll go ahead and test my variac and
post what I find, regardless of what "Mr. Perfect" does.

Can't wait.

---
But, poor baby, you'll have to.

Forever!


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

 

[Jim Thompson]

On Sat, 13 Apr 2013 14:00:19 -0500, John Fields
<jfields@austininstruments.com> wrote:

On Sat, 13 Apr 2013 08:57:04 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Sat, 13 Apr 2013 05:49:50 -0500, John Fields <jfields@austininstruments.com
wrote:

On Fri, 12 Apr 2013 18:39:48 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Fri, 12 Apr 2013 01:31:53 -0400, "P E Schoen" <paul@peschoen.com> wrote:

"John Larkin" wrote in message
news:s86em81bhs0q8glvlh9mnh0skad6its081@4ax.com...

On Thu, 11 Apr 2013 14:34:21 -0500, John Fields
jfields@austininstruments.com> wrote:

Because "Failure mode" is a bit too harsh, I think, since they're
designed to take a lot of abuse.

However, if you want to play specmanship, we might talk about the
increase of turn-to-turn leakage reactance with respect to frequency,
and the leakage from winding to core.

What in the world could all that word salad blather possibly mean?

What, specifically, is a Variac going to do as the frequency is
increased from 60 Hz to 1 KHz?

This is getting rather silly, and JF seems to be grasping at straws.

---
I just want to see some real test data.

You claim to have all te necessary gear. If you e=want to see test data, why
don't you do it yourself? If I did measure a Variac up into the KHz, you'd most
likely not like the results and accuse me of faking the data.

---
Not at all.

What I object to is your making claims which you refuse to back up
with real-world data which can be replicated.

Sort of like Joseph Newman, who's from your neck of the woods as I
understand it.

Then there's the matter of you apparently ignoring my request for your
variac's manufacturer and model/part number.

Why would you do that?
---

Silly, useless old fart.

---
Wow, the anal references which you earlier found repugnant now seem to
emanating from your camp.
---

Toroids are often used for high quality audio and high efficiency
power transformers because they have much less leakage inductance
than EI and other core types. Here is some information on toroidal
power transformers where the corner frequency is about 50 kHz:
http://www.toruspower.com/nbt-narrow-bandwidth-technology/

---
Fixed "n" toroidal high quality audio and power transformers aren't
the same animals as variable "n" variacs, so equating one to the other
is a little risky, I think.
---

Even if the laminations in a variac are optimized for cost at 60 Hz, core losses
will still be moderate at, say, 1 KHz. The OP was concerned with 60 Hz plus
harmonics, so in that case the HF component would be small, so core loss is not
an issue at all.

---
You posted earlier that the bandwidth of the variac would be high
enough to pass the harmonics, and now you post that the harmonic
content will be small, without even having a clue as to the output
waveform of the variac.

Why don't you just test your variac and put the whole thing to rest?
---

At high line frequencies, leakage inductance will soften up the load regulation
a bit, but toroids have very low leakage inductance. With the Variac in/out
ratio anywhere near 1.0, inductive effects are still smaller.

Yes, JF is flailing, tossing around words as if he understands what they mean.

---
Whatever you say, John.
---

Even the lowest corner frequency was 3 kHz, but this was in the context of a
low pass filter where it was desired to attenuate higher frequency
components of power line noise. But it seems evident that these toroids work
well at high audio frequencies.

---
If it seems evident that those toroids work well at high audio
frequencies, consideration should be given to the fact that they
aren't variacs, and that they do so by design.
---

My own measurements were supposed to
determine if a given core size for 60 Hz could be used at higher frequencies
and correspondingly higher voltage and power levels.

The results indicate that there will be higher core loss at higher frequency
which may be proportional to the square root of frequency, so if my toroid
has 0.5% core loss at 60 Hz it may have 1% at 240 Hz and 2% at 1 kHz and 4%
at 4 kHz. But that is also accompanied by total power capacity increase from
80 VA at 60 Hz to 1.3 kVA at 1 KHz. Thus there may be 26W of core loss, but
that may be acceptable if the smaller size is a major advantage.

---
But that's for transformers that aren't variacs.

Tell ya what I'm going to do: I'll go ahead and test my variac and
post what I find, regardless of what "Mr. Perfect" does.

Can't wait.

---
But, poor baby, you'll have to.

Borrowing an epithet from Slowman... John "NOLA white trash" Larkin is
a "gormless asshole grommet" >:-}

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[Jim Thompson]

On Sat, 13 Apr 2013 14:51:22 -0500, John Fields
<jfields@austininstruments.com> wrote:

On Sat, 13 Apr 2013 11:41:28 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:


He won't actually do it. And if he did, the stuff he measures won't make sense.

---
To you, perhaps, since it may be at odds with what you want to hear,
but I'm intrigued...

Why don't you run your own tests and present them as prima facie
evidence to support your position instead of threatening to shoot down
everyone else's positions as being untenable?

Present data which can actually be confirmed or denied? Give me a
break. Hell will freeze over first.

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[John Fields]

On Sat, 13 Apr 2013 13:24:59 -0700, John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Sat, 13 Apr 2013 14:00:19 -0500, John Fields <jfields@austininstruments.com
wrote:

On Sat, 13 Apr 2013 08:57:04 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Sat, 13 Apr 2013 05:49:50 -0500, John Fields <jfields@austininstruments.com
wrote:

On Fri, 12 Apr 2013 18:39:48 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Fri, 12 Apr 2013 01:31:53 -0400, "P E Schoen" <paul@peschoen.com> wrote:

"John Larkin" wrote in message
news:s86em81bhs0q8glvlh9mnh0skad6its081@4ax.com...

On Thu, 11 Apr 2013 14:34:21 -0500, John Fields
jfields@austininstruments.com> wrote:

Because "Failure mode" is a bit too harsh, I think, since they're
designed to take a lot of abuse.

However, if you want to play specmanship, we might talk about the
increase of turn-to-turn leakage reactance with respect to frequency,
and the leakage from winding to core.

What in the world could all that word salad blather possibly mean?

What, specifically, is a Variac going to do as the frequency is
increased from 60 Hz to 1 KHz?

This is getting rather silly, and JF seems to be grasping at straws.

---
I just want to see some real test data.

You claim to have all te necessary gear. If you e=want to see test data, why
don't you do it yourself? If I did measure a Variac up into the KHz, you'd most
likely not like the results and accuse me of faking the data.

---
Not at all.

What I object to is your making claims which you refuse to back up
with real-world data which can be replicated.

Sort of like Joseph Newman, who's from your neck of the woods as I
understand it.

Then there's the matter of you apparently ignoring my request for your
variac's manufacturer and model/part number.

Why would you do that?
---

Silly, useless old fart.

---
Wow, the anal references which you earlier found repugnant now seem to
emanating from your camp.
---

Toroids are often used for high quality audio and high efficiency
power transformers because they have much less leakage inductance
than EI and other core types. Here is some information on toroidal
power transformers where the corner frequency is about 50 kHz:
http://www.toruspower.com/nbt-narrow-bandwidth-technology/

---
Fixed "n" toroidal high quality audio and power transformers aren't
the same animals as variable "n" variacs, so equating one to the other
is a little risky, I think.
---

Even if the laminations in a variac are optimized for cost at 60 Hz, core losses
will still be moderate at, say, 1 KHz. The OP was concerned with 60 Hz plus
harmonics, so in that case the HF component would be small, so core loss is not
an issue at all.

---
You posted earlier that the bandwidth of the variac would be high
enough to pass the harmonics, and now you post that the harmonic
content will be small, without even having a clue as to the output
waveform of the variac.

Why don't you just test your variac and put the whole thing to rest?
---

At high line frequencies, leakage inductance will soften up the load regulation
a bit, but toroids have very low leakage inductance. With the Variac in/out
ratio anywhere near 1.0, inductive effects are still smaller.

Yes, JF is flailing, tossing around words as if he understands what they mean.

---
Whatever you say, John.
---

Even the lowest corner frequency was 3 kHz, but this was in the context of a
low pass filter where it was desired to attenuate higher frequency
components of power line noise. But it seems evident that these toroids work
well at high audio frequencies.

---
If it seems evident that those toroids work well at high audio
frequencies, consideration should be given to the fact that they
aren't variacs, and that they do so by design.
---

My own measurements were supposed to
determine if a given core size for 60 Hz could be used at higher frequencies
and correspondingly higher voltage and power levels.

The results indicate that there will be higher core loss at higher frequency
which may be proportional to the square root of frequency, so if my toroid
has 0.5% core loss at 60 Hz it may have 1% at 240 Hz and 2% at 1 kHz and 4%
at 4 kHz. But that is also accompanied by total power capacity increase from
80 VA at 60 Hz to 1.3 kVA at 1 KHz. Thus there may be 26W of core loss, but
that may be acceptable if the smaller size is a major advantage.

---
But that's for transformers that aren't variacs.

Tell ya what I'm going to do: I'll go ahead and test my variac and
post what I find, regardless of what "Mr. Perfect" does.

Can't wait.

---
But, poor baby, you'll have to.

Forever!

---
Well, you don't seem to have a good handle on what constitutes the
infinite and, in the same vein, the infinitesimal, so the wait may be
shorter or longer than you'd like it to be.

As for the experiment, I expect to design, test it, and post the
results within the next two weeks, so there's your window.

--
JF

 

[John Larkin]

On Mon, 15 Apr 2013 16:52:45 -0500, John Fields
<jfields@austininstruments.com> wrote:

On Sat, 13 Apr 2013 13:24:59 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Sat, 13 Apr 2013 14:00:19 -0500, John Fields <jfields@austininstruments.com
wrote:

On Sat, 13 Apr 2013 08:57:04 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Sat, 13 Apr 2013 05:49:50 -0500, John Fields <jfields@austininstruments.com
wrote:

On Fri, 12 Apr 2013 18:39:48 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Fri, 12 Apr 2013 01:31:53 -0400, "P E Schoen" <paul@peschoen.com> wrote:

"John Larkin" wrote in message
news:s86em81bhs0q8glvlh9mnh0skad6its081@4ax.com...

On Thu, 11 Apr 2013 14:34:21 -0500, John Fields
jfields@austininstruments.com> wrote:

Because "Failure mode" is a bit too harsh, I think, since they're
designed to take a lot of abuse.

However, if you want to play specmanship, we might talk about the
increase of turn-to-turn leakage reactance with respect to frequency,
and the leakage from winding to core.

What in the world could all that word salad blather possibly mean?

What, specifically, is a Variac going to do as the frequency is
increased from 60 Hz to 1 KHz?

This is getting rather silly, and JF seems to be grasping at straws.

---
I just want to see some real test data.

You claim to have all te necessary gear. If you e=want to see test data, why
don't you do it yourself? If I did measure a Variac up into the KHz, you'd most
likely not like the results and accuse me of faking the data.

---
Not at all.

What I object to is your making claims which you refuse to back up
with real-world data which can be replicated.

Sort of like Joseph Newman, who's from your neck of the woods as I
understand it.

Then there's the matter of you apparently ignoring my request for your
variac's manufacturer and model/part number.

Why would you do that?
---

Silly, useless old fart.

---
Wow, the anal references which you earlier found repugnant now seem to
emanating from your camp.
---

Toroids are often used for high quality audio and high efficiency
power transformers because they have much less leakage inductance
than EI and other core types. Here is some information on toroidal
power transformers where the corner frequency is about 50 kHz:
http://www.toruspower.com/nbt-narrow-bandwidth-technology/

---
Fixed "n" toroidal high quality audio and power transformers aren't
the same animals as variable "n" variacs, so equating one to the other
is a little risky, I think.
---

Even if the laminations in a variac are optimized for cost at 60 Hz, core losses
will still be moderate at, say, 1 KHz. The OP was concerned with 60 Hz plus
harmonics, so in that case the HF component would be small, so core loss is not
an issue at all.

---
You posted earlier that the bandwidth of the variac would be high
enough to pass the harmonics, and now you post that the harmonic
content will be small, without even having a clue as to the output
waveform of the variac.

Why don't you just test your variac and put the whole thing to rest?
---

At high line frequencies, leakage inductance will soften up the load regulation
a bit, but toroids have very low leakage inductance. With the Variac in/out
ratio anywhere near 1.0, inductive effects are still smaller.

Yes, JF is flailing, tossing around words as if he understands what they mean.

---
Whatever you say, John.
---

Even the lowest corner frequency was 3 kHz, but this was in the context of a
low pass filter where it was desired to attenuate higher frequency
components of power line noise. But it seems evident that these toroids work
well at high audio frequencies.

---
If it seems evident that those toroids work well at high audio
frequencies, consideration should be given to the fact that they
aren't variacs, and that they do so by design.
---

My own measurements were supposed to
determine if a given core size for 60 Hz could be used at higher frequencies
and correspondingly higher voltage and power levels.

The results indicate that there will be higher core loss at higher frequency
which may be proportional to the square root of frequency, so if my toroid
has 0.5% core loss at 60 Hz it may have 1% at 240 Hz and 2% at 1 kHz and 4%
at 4 kHz. But that is also accompanied by total power capacity increase from
80 VA at 60 Hz to 1.3 kVA at 1 KHz. Thus there may be 26W of core loss, but
that may be acceptable if the smaller size is a major advantage.

---
But that's for transformers that aren't variacs.

Tell ya what I'm going to do: I'll go ahead and test my variac and
post what I find, regardless of what "Mr. Perfect" does.

Can't wait.

---
But, poor baby, you'll have to.

Forever!

---
Well, you don't seem to have a good handle on what constitutes the
infinite and, in the same vein, the infinitesimal, so the wait may be
shorter or longer than you'd like it to be.

As for the experiment, I expect to design, test it, and post the
results within the next two weeks, so there's your window.

Great. Should be interesting.


--

John Larkin Highland Technology, Inc

jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation

 

[John Fields]

On Mon, 15 Apr 2013 18:09:29 -0700, John Larkin
<jlarkin@highlandtechnology.com> wrote:

On Mon, 15 Apr 2013 16:52:45 -0500, John Fields
jfields@austininstruments.com> wrote:

As for the experiment, I expect to design, test it, and post the
results within the next two weeks, so there's your window.

Great. Should be interesting.

---
I hope so.

In the meantime, what can you tell us about _your_ variac?

Just manufacturer and part number would be nice, and a link to a data
sheet would be even better.

What do you say; can/will you post either?

--
JF

 

[John Larkin]

On Tue, 16 Apr 2013 14:16:40 -0500, John Fields
<jfields@austininstruments.com> wrote:

On Mon, 15 Apr 2013 18:09:29 -0700, John Larkin
jlarkin@highlandtechnology.com> wrote:

On Mon, 15 Apr 2013 16:52:45 -0500, John Fields
jfields@austininstruments.com> wrote:

As for the experiment, I expect to design, test it, and post the
results within the next two weeks, so there's your window.

Great. Should be interesting.

---
I hope so.

In the meantime, what can you tell us about _your_ variac?

Just manufacturer and part number would be nice, and a link to a data
sheet would be even better.

What do you say; can/will you post either?

The one in the engineering lab is a Calrad 45-470, rated 5 amps. We've
had it for ages.


--

John Larkin Highland Technology, Inc

jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation

 

[P E Schoen]

"John Larkin" wrote in message
news:1hprm8906ime83bvfdh63ohvodr3kh84mg@4ax.com...

The one in the engineering lab is a Calrad 45-470, rated 5 amps.
We've had it for ages.

I couldn't find anything on that model. Is it GenRad (General Radio)? Is it
really old like this:
http://www.uvm.edu/~dahammon/museum/generalradiovariac.html

I have a large quantity of Staco and Superior "variacs". The Superior 120V
5A is model 21, and the Staco equivalent is 501. I also have some larger
240V units rated at 3.5 amps (Superior 216)
http://www.danaherspecialtyproducts.com/uploadedFiles/Siteroot/Superior_Electric/Products_and_Solutions/POWERSTAT%C2%AE_Variable_Transformers/116-217(pg10-13).PDF

The 216/217 versions (240V) are specified for full output to 2kHz. The
116/117 versions are derated about 7% from 1.6 kHz to 2 kHz.

BTW, when I tested the toroid I rewound (which may have been from a variac),
I went to 16 kHz. And that was a square wave, which still had very fast
rise/fall times. But to be fair it was not putting out much current.

Paul

 

[John Larkin]

On Tue, 16 Apr 2013 22:54:53 -0400, "P E Schoen" <paul@peschoen.com> wrote:

"John Larkin" wrote in message
news:1hprm8906ime83bvfdh63ohvodr3kh84mg@4ax.com...

The one in the engineering lab is a Calrad 45-470, rated 5 amps.
We've had it for ages.

I couldn't find anything on that model. Is it GenRad (General Radio)? Is it
really old like this:
http://www.uvm.edu/~dahammon/museum/generalradiovariac.html

Not really old. Calrad mostly rebrands Asian stuff.

http://www.calradstore.com/calrad.html

Wiki says that "Variac" dates from 1934. I can't imagine that there is a lot of
variation among Variac clones any more.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

 

[T]

In article <wtH6t.280368$Nq4.66842@newsfe21.iad>, spamtrap@dcorp.com
says...

Two occasional (electrical) causes of hum in electric motors (specifically
ceiling fans) are overvoltage and a noisy sine-wave.

If a US home is measured over 127VAC the local power utility will often
install a line conditioner. If a home is measured at 125VAC, in most cases
the power utility states that it is "within tolerances".

Tracking the source of line noise on 120VAC is often trial and error and
cannot always identify a single culprit. O'scopes are not commonly carried
by the installers. But I have documented a few overvoltage situations where
the line noise was also present; and I suspect creating some of the measured
overrvoltage.

I would like a device, that can reduce 125VAC voltage by 10% while
maintaining a smooth sine waveform. The last time I researched 120V
transformers for a 10% voltage reduction, they were too large (4"x 4" x 4")
for my purposes. Optimally I would like to this device to fit within a
"pancake box" outlet box, but even a 4" octagon outlet box.

Are there any new developments in small sized transformers capable of doing
this?
Does anybody have any ideas how else this could be accomplished?

Thanks!
Scott
Dunedin FL

Around here all the outlets put out 125VAC. Works with pretty much
everything.

 

[P E Schoen]

"John Larkin" wrote in message
news:md4sm891hivhkujpvvr7sjk65gm4nkphuo@4ax.com...

Not really old. Calrad mostly rebrands Asian stuff.

http://www.calradstore.com/calrad.html

Wiki says that "Variac" dates from 1934. I can't imagine that there is a
lot of variation among Variac clones any more.

Hey, where is the test data promised by John Fields? Once I recover from hip
replacement surgery** I plan to run some tests on one or more of the
"variacs" I have, some of which are actually just the wound cores without
the sliders, rated 9.5A at 240 VAC. The reason I have a huge pile of them
(15-20 pieces of Staco 1520) is that they were built into a product that
assumed their rating was correct and could be used at the published overload
duty cycles. But they failed catastrophically and we got a settlement from
Staco so we could purchase larger units that met our needs. I performed the
testing and proved that the special thin brush (as opposed to the more
rugged wedge shape) would overheat and crack and the brush holder would drop
onto the turns, causing a spectacular short.

http://variac.com/staco_variable_transformer_1510_.htm

For this model with the same core, the 120V version was rated at 15 amps,
and one would expect the 240V version to be half that at 7.5A. For other
models, such as the 1010/1020, the 240V version is rated at less than half
the current (3.5A vs 10A).

http://www.variac.com/staco_variable_transformer_1000_1200.htm

Anyway, as you can see, these units are fully rated to 2 kHz, and I'm
betting they can work respectably to 10kHz or more. The name brand variacs
are probably wound with high quality thin silicon steel laminations with
good high frequency response. The cheapo Chinese brands selling at about 1/4
the price of Staco and Superior are probably made of cheaper materials. But
I think they will just run a little hotter or noisier but OK up to at least
400 Hz and probably 1-2 kHz or more.

I'll do some tests when I'm able to get around better.

**JF, what's your excuse?

Paul

 

[John Larkin]

On Fri, 10 May 2013 15:43:23 -0400, "P E Schoen" <paul@peschoen.com> wrote:

"John Larkin" wrote in message
news:md4sm891hivhkujpvvr7sjk65gm4nkphuo@4ax.com...

Not really old. Calrad mostly rebrands Asian stuff.

http://www.calradstore.com/calrad.html

Wiki says that "Variac" dates from 1934. I can't imagine that there is a
lot of variation among Variac clones any more.

Hey, where is the test data promised by John Fields?

I've asked that question myself.

Once I recover from hip

replacement surgery** I plan to run some tests on one or more of the
"variacs" I have, some of which are actually just the wound cores without
the sliders, rated 9.5A at 240 VAC. The reason I have a huge pile of them
(15-20 pieces of Staco 1520) is that they were built into a product that
assumed their rating was correct and could be used at the published overload
duty cycles. But they failed catastrophically and we got a settlement from
Staco so we could purchase larger units that met our needs. I performed the
testing and proved that the special thin brush (as opposed to the more
rugged wedge shape) would overheat and crack and the brush holder would drop
onto the turns, causing a spectacular short.

http://variac.com/staco_variable_transformer_1510_.htm

For this model with the same core, the 120V version was rated at 15 amps,
and one would expect the 240V version to be half that at 7.5A. For other
models, such as the 1010/1020, the 240V version is rated at less than half
the current (3.5A vs 10A).

http://www.variac.com/staco_variable_transformer_1000_1200.htm

Anyway, as you can see, these units are fully rated to 2 kHz, and I'm
betting they can work respectably to 10kHz or more. The name brand variacs
are probably wound with high quality thin silicon steel laminations with
good high frequency response. The cheapo Chinese brands selling at about 1/4
the price of Staco and Superior are probably made of cheaper materials. But
I think they will just run a little hotter or noisier but OK up to at least
400 Hz and probably 1-2 kHz or more.

I'll do some tests when I'm able to get around better.

Catch up on some good books.

**JF, what's your excuse?

I suspect he doesn't know what to measure.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

 

[John Fields]

On Fri, 10 May 2013 15:43:23 -0400, "P E Schoen" <paul@peschoen.com>
wrote:

Hey, where is the test data promised by John Fields?

---
Just lazy, plus there doesn't seem to be a pressing need for it, and
posting the data will only lead to another pointless argument with
Larkin, so why even bother?

--
JF