In rec.radio.amateur.boatanchors gareth wrote:
These LED replacements for 240V mains lamps; if one were to
open them, would one find a high voltage regulator suitable for
some of our valve experiments and repairs?

As the regulators are potted in and would be difficult to remove, and
since LED's run on voltages on the order of 2-3 volts, no.

How many 3 volt valves can you name?



--
Jim Pennino

On Fri, 28 Nov 2014, wrote:

In rec.radio.amateur.boatanchors gareth wrote:
These LED replacements for 240V mains lamps; if one were to
open them, would one find a high voltage regulator suitable for
some of our valve experiments and repairs?

As the regulators are potted in and would be difficult to remove, and
since LED's run on voltages on the order of 2-3 volts, no.

How many 3 volt valves can you name?

I think that point was that if a regulator was used to drop the line
voltage to those 3volts, it could handle high voltage input. The probably
false assumption is that the regulator would be variable from some very
high output voltage to some very low output voltage, so one could use it
for tubes by making that adjustment.

A lot of IC regulators can't handle high voltage. If nothing else, nobody
saw the need, it was the solid state age. So dissipation issues aside,
most regulators expect at most a relatively low DC voltage input.

Of course, one can run tubes on low voltage. The Collins 75S receiver
line apparently kept plat voltage relatively low (somewhere around 120v if
I remember right) which had certain advantages. One can run regular tubes
at 12VDC on the plate, there were some articles in Popular Electronics
about this, calling them "starved circuits". Or there were those tubes
designed to run off 12VDC for those hybrid car radios, a last gasp before
transistors took over completely.

Though, 3VDC does seem a tad low.

Michael

In rec.radio.amateur.boatanchors Michael Black wrote:
On Fri, 28 Nov 2014, wrote:

In rec.radio.amateur.boatanchors gareth wrote:
These LED replacements for 240V mains lamps; if one were to
open them, would one find a high voltage regulator suitable for
some of our valve experiments and repairs?

As the regulators are potted in and would be difficult to remove, and
since LED's run on voltages on the order of 2-3 volts, no.

How many 3 volt valves can you name?

I think that point was that if a regulator was used to drop the line
voltage to those 3volts, it could handle high voltage input. The probably
false assumption is that the regulator would be variable from some very
high output voltage to some very low output voltage, so one could use it
for tubes by making that adjustment.

Given that manufacturers want the least cost in a product, and the
regulator in a light bulb would have no need for a variable regulator,
and that these things are made in the millions, it would be extremely
silly to assume that the regulator is anything other than a fixed
regulator for LED's and is designed to handle the load of some fixed
number of LED's.

A lot of IC regulators can't handle high voltage. If nothing else, nobody
saw the need, it was the solid state age. So dissipation issues aside,
most regulators expect at most a relatively low DC voltage input.

True for IC regulators. Hoever high voltage transistors exist these
days which makes designing a high voltage regulator pretty trivial.

Of course, one can run tubes on low voltage. The Collins 75S receiver
line apparently kept plat voltage relatively low (somewhere around 120v if
I remember right) which had certain advantages. One can run regular tubes
at 12VDC on the plate, there were some articles in Popular Electronics
about this, calling them "starved circuits". Or there were those tubes
designed to run off 12VDC for those hybrid car radios, a last gasp before
transistors took over completely.

Though, 3VDC does seem a tad low.

When they were running regular tubes on "low voltage", that was voltages
around 100 V as opposed to 200 to 300 Volts.

The 12 Volt tubes are long gone and not that great to begin with.

Michael

--
Jim Pennino

On 11/28/2014 4:11 PM, wrote:
In rec.radio.amateur.boatanchors Michael Black wrote:
On Fri, 28 Nov 2014, wrote:

In rec.radio.amateur.boatanchors gareth wrote:
These LED replacements for 240V mains lamps; if one were to
open them, would one find a high voltage regulator suitable for
some of our valve experiments and repairs?

As the regulators are potted in and would be difficult to remove, and
since LED's run on voltages on the order of 2-3 volts, no.

How many 3 volt valves can you name?

I think that point was that if a regulator was used to drop the line
voltage to those 3volts, it could handle high voltage input. The probably
false assumption is that the regulator would be variable from some very
high output voltage to some very low output voltage, so one could use it
for tubes by making that adjustment.

Given that manufacturers want the least cost in a product, and the
regulator in a light bulb would have no need for a variable regulator,
and that these things are made in the millions, it would be extremely
silly to assume that the regulator is anything other than a fixed
regulator for LED's and is designed to handle the load of some fixed
number of LED's.


Once again, incorrect. Have you ever heard of "dimmable LED bulbs"?
How do you dim without an adjustable regulator?

A lot of IC regulators can't handle high voltage. If nothing else, nobody
saw the need, it was the solid state age. So dissipation issues aside,
most regulators expect at most a relatively low DC voltage input.

True for IC regulators. Hoever high voltage transistors exist these
days which makes designing a high voltage regulator pretty trivial.


Sure. But how do you handle the current requirements without some kind
of transformer?

snip

--
==================
Remove the "x" from my email address
Jerry, AI0K

==================

In rec.radio.amateur.boatanchors Jerry Stuckle wrote:
On 11/28/2014 4:11 PM, wrote:
In rec.radio.amateur.boatanchors Michael Black wrote:
On Fri, 28 Nov 2014, wrote:

In rec.radio.amateur.boatanchors gareth wrote:
These LED replacements for 240V mains lamps; if one were to
open them, would one find a high voltage regulator suitable for
some of our valve experiments and repairs?

As the regulators are potted in and would be difficult to remove, and
since LED's run on voltages on the order of 2-3 volts, no.

How many 3 volt valves can you name?

I think that point was that if a regulator was used to drop the line
voltage to those 3volts, it could handle high voltage input. The probably
false assumption is that the regulator would be variable from some very
high output voltage to some very low output voltage, so one could use it
for tubes by making that adjustment.

Given that manufacturers want the least cost in a product, and the
regulator in a light bulb would have no need for a variable regulator,
and that these things are made in the millions, it would be extremely
silly to assume that the regulator is anything other than a fixed
regulator for LED's and is designed to handle the load of some fixed
number of LED's.


Once again, incorrect. Have you ever heard of "dimmable LED bulbs"?
How do you dim without an adjustable regulator?

You do realize that a dimmable light bulb is dimmed by changeing the
supply voltage and not by anything else connected to the bulb?

To specifically answer your question, you design a regulator who's output
is some precentage of the raw input as opposed to a regulator who's
output is always equal to some reference voltage.

And to be yet more specific, since LED brightness is proportional to
current and resistors would waste power, the regulator would be a
current regulator with an average current output proportional to the
raw input voltage.

A lot of IC regulators can't handle high voltage. If nothing else, nobody
saw the need, it was the solid state age. So dissipation issues aside,
most regulators expect at most a relatively low DC voltage input.

True for IC regulators. Hoever high voltage transistors exist these
days which makes designing a high voltage regulator pretty trivial.


Sure. But how do you handle the current requirements without some kind
of transformer?

Well, assuming you want some voltage greater than the wall plug maximum,
the need for a transformer is pretty much a given unless some sort of
voltage multiplying rectifier is sufficient for the need, which is
where the current requirement becomes relevant.

However, the subject was high voltage regulators, not where does the
raw high voltage come from.



--
Jim Pennino

On 11/28/2014 5:24 PM, wrote:
In rec.radio.amateur.boatanchors Jerry Stuckle wrote:
On 11/28/2014 4:11 PM, wrote:
In rec.radio.amateur.boatanchors Michael Black wrote:
On Fri, 28 Nov 2014, wrote:

In rec.radio.amateur.boatanchors gareth wrote:
These LED replacements for 240V mains lamps; if one were to
open them, would one find a high voltage regulator suitable for
some of our valve experiments and repairs?

As the regulators are potted in and would be difficult to remove, and
since LED's run on voltages on the order of 2-3 volts, no.

How many 3 volt valves can you name?

I think that point was that if a regulator was used to drop the line
voltage to those 3volts, it could handle high voltage input. The probably
false assumption is that the regulator would be variable from some very
high output voltage to some very low output voltage, so one could use it
for tubes by making that adjustment.

Given that manufacturers want the least cost in a product, and the
regulator in a light bulb would have no need for a variable regulator,
and that these things are made in the millions, it would be extremely
silly to assume that the regulator is anything other than a fixed
regulator for LED's and is designed to handle the load of some fixed
number of LED's.


Once again, incorrect. Have you ever heard of "dimmable LED bulbs"?
How do you dim without an adjustable regulator?

You do realize that a dimmable light bulb is dimmed by changeing the
supply voltage and not by anything else connected to the bulb?


For incandescent, yes. But not for LED bulbs. If that were the case,
why would some LED bulbs be dimmable and others not?

To specifically answer your question, you design a regulator who's output
is some precentage of the raw input as opposed to a regulator who's
output is always equal to some reference voltage.


Again, it all depends.

And to be yet more specific, since LED brightness is proportional to
current and resistors would waste power, the regulator would be a
current regulator with an average current output proportional to the
raw input voltage.


Then why can't you use standard incandescent dimmers with LED bulbs?

A lot of IC regulators can't handle high voltage. If nothing else, nobody
saw the need, it was the solid state age. So dissipation issues aside,
most regulators expect at most a relatively low DC voltage input.

True for IC regulators. Hoever high voltage transistors exist these
days which makes designing a high voltage regulator pretty trivial.


Sure. But how do you handle the current requirements without some kind
of transformer?

Well, assuming you want some voltage greater than the wall plug maximum,
the need for a transformer is pretty much a given unless some sort of
voltage multiplying rectifier is sufficient for the need, which is
where the current requirement becomes relevant.

However, the subject was high voltage regulators, not where does the
raw high voltage come from.


And where do you get the current necessary to supply the LEDs in the
bulbs? A typical LED required around 3V (usually 2.7V to 3.3V,
depending on the LED)? A 9 watt LED would require 3 amps of current.
Or, if the LEDs were in series, something less. But without a
transformer, the current would still exceed that of an incandescent bulb.

You obviously are unfamiliar with the structure of LED bulbs.

--
==================
Remove the "x" from my email address
Jerry, AI0K

==================

On 11/28/2014 6:16 PM, Jerry Stuckle wrote:
On 11/28/2014 5:24 PM, wrote:
In rec.radio.amateur.boatanchors Jerry Stuckle wrote:
On 11/28/2014 4:11 PM, wrote:
In rec.radio.amateur.boatanchors Michael Black wrote:
On Fri, 28 Nov 2014, wrote:

In rec.radio.amateur.boatanchors gareth wrote:
These LED replacements for 240V mains lamps; if one were to
open them, would one find a high voltage regulator suitable for
some of our valve experiments and repairs?

As the regulators are potted in and would be difficult to remove, and
since LED's run on voltages on the order of 2-3 volts, no.

How many 3 volt valves can you name?

I think that point was that if a regulator was used to drop the line
voltage to those 3volts, it could handle high voltage input. The probably
false assumption is that the regulator would be variable from some very
high output voltage to some very low output voltage, so one could use it
for tubes by making that adjustment.

Given that manufacturers want the least cost in a product, and the
regulator in a light bulb would have no need for a variable regulator,
and that these things are made in the millions, it would be extremely
silly to assume that the regulator is anything other than a fixed
regulator for LED's and is designed to handle the load of some fixed
number of LED's.


Once again, incorrect. Have you ever heard of "dimmable LED bulbs"?
How do you dim without an adjustable regulator?

You do realize that a dimmable light bulb is dimmed by changeing the
supply voltage and not by anything else connected to the bulb?


For incandescent, yes. But not for LED bulbs. If that were the case,
why would some LED bulbs be dimmable and others not?

To specifically answer your question, you design a regulator who's output
is some precentage of the raw input as opposed to a regulator who's
output is always equal to some reference voltage.


Again, it all depends.

And to be yet more specific, since LED brightness is proportional to
current and resistors would waste power, the regulator would be a
current regulator with an average current output proportional to the
raw input voltage.


Then why can't you use standard incandescent dimmers with LED bulbs?

A lot of IC regulators can't handle high voltage. If nothing else, nobody
saw the need, it was the solid state age. So dissipation issues aside,
most regulators expect at most a relatively low DC voltage input.

True for IC regulators. Hoever high voltage transistors exist these
days which makes designing a high voltage regulator pretty trivial.


Sure. But how do you handle the current requirements without some kind
of transformer?

Well, assuming you want some voltage greater than the wall plug maximum,
the need for a transformer is pretty much a given unless some sort of
voltage multiplying rectifier is sufficient for the need, which is
where the current requirement becomes relevant.

However, the subject was high voltage regulators, not where does the
raw high voltage come from.


And where do you get the current necessary to supply the LEDs in the
bulbs? A typical LED required around 3V (usually 2.7V to 3.3V,
depending on the LED)? A 9 watt LED would require 3 amps of current.
Or, if the LEDs were in series, something less. But without a
transformer, the current would still exceed that of an incandescent bulb.

You obviously are unfamiliar with the structure of LED bulbs.

You two are both speculating and have limited information to base either
of your opinions on. Jim says,

You do realize that a dimmable light bulb is dimmed by changeing the
supply voltage and not by anything else connected to the bulb?

which is not correct in that most dimmers work by reducing the phase
angle of the applied AC or to reduce noise some simply don't turn on for
entire half cycles.

Jerry says,

Then why can't you use standard incandescent dimmers with LED bulbs?

Which is wrong because you can use "standard" dimmers, but the LED bulb
has to be designed for it.

Try reading a little...

http://www.ledsmagazine.com/articles...-magazine.html

--

Rick

In rec.radio.amateur.boatanchors Jerry Stuckle wrote:
On 11/28/2014 5:24 PM, wrote:
In rec.radio.amateur.boatanchors Jerry Stuckle wrote:
On 11/28/2014 4:11 PM, wrote:
In rec.radio.amateur.boatanchors Michael Black wrote:
On Fri, 28 Nov 2014, wrote:

In rec.radio.amateur.boatanchors gareth wrote:
These LED replacements for 240V mains lamps; if one were to
open them, would one find a high voltage regulator suitable for
some of our valve experiments and repairs?

As the regulators are potted in and would be difficult to remove, and
since LED's run on voltages on the order of 2-3 volts, no.

How many 3 volt valves can you name?

I think that point was that if a regulator was used to drop the line
voltage to those 3volts, it could handle high voltage input. The probably
false assumption is that the regulator would be variable from some very
high output voltage to some very low output voltage, so one could use it
for tubes by making that adjustment.

Given that manufacturers want the least cost in a product, and the
regulator in a light bulb would have no need for a variable regulator,
and that these things are made in the millions, it would be extremely
silly to assume that the regulator is anything other than a fixed
regulator for LED's and is designed to handle the load of some fixed
number of LED's.


Once again, incorrect. Have you ever heard of "dimmable LED bulbs"?
How do you dim without an adjustable regulator?

You do realize that a dimmable light bulb is dimmed by changeing the
supply voltage and not by anything else connected to the bulb?


For incandescent, yes. But not for LED bulbs. If that were the case,
why would some LED bulbs be dimmable and others not?

Yes, for LED bulbs.

However, the simplest way to see that the light output is controlled
by the applied voltage is to simply look at the base of a dimmable
bulb and note that there are only two connections; no third connection
for a control, just the same as all other light bulbs.

Some are dimmable and some are not because it takes more parts to make
a dimmable bulb and the demand for them is less than that for non-dimmable
bulbs.

To specifically answer your question, you design a regulator who's output
is some precentage of the raw input as opposed to a regulator who's
output is always equal to some reference voltage.


Again, it all depends.

Nope; light bulbs run at a rated voltage which is the standard voltage
for the country in which they are sold; US light bulbs are rated for
120v, UK bulbs for whatever the voltage is over there, I think 240V.

You are just arguing for the sake of arguing.

And to be yet more specific, since LED brightness is proportional to
current and resistors would waste power, the regulator would be a
current regulator with an average current output proportional to the
raw input voltage.


Then why can't you use standard incandescent dimmers with LED bulbs?

You can if the bulb is specified as dimmable; some are, and some are not
and they all use the standard two connection E26 base.

A lot of IC regulators can't handle high voltage. If nothing else, nobody
saw the need, it was the solid state age. So dissipation issues aside,
most regulators expect at most a relatively low DC voltage input.

True for IC regulators. Hoever high voltage transistors exist these
days which makes designing a high voltage regulator pretty trivial.


Sure. But how do you handle the current requirements without some kind
of transformer?

Well, assuming you want some voltage greater than the wall plug maximum,
the need for a transformer is pretty much a given unless some sort of
voltage multiplying rectifier is sufficient for the need, which is
where the current requirement becomes relevant.

However, the subject was high voltage regulators, not where does the
raw high voltage come from.


And where do you get the current necessary to supply the LEDs in the
bulbs? A typical LED required around 3V (usually 2.7V to 3.3V,
depending on the LED)? A 9 watt LED would require 3 amps of current.
Or, if the LEDs were in series, something less. But without a
transformer, the current would still exceed that of an incandescent bulb.

None of this has anything to do with high voltage.

The standard US wall outlet is rated at 15 Amps.

A Phillips A21 75W replacement LED bulb draws 15W at 120V (0.125A)
and is dimmable.

http://www.usa.philips.com/c-p/04667...white-dimmable

You obviously are unfamiliar with the structure of LED bulbs.

You obiously have never noticed that the base of an LED bulb is identical
to that of an incandescent, i.e. two wire E26 base, and that standard wall
outlets in the US are 15 Amps.


--
Jim Pennino

Jerry Stuckle wrote:
For incandescent, yes. But not for LED bulbs. If that were the case,
why would some LED bulbs be dimmable and others not?

"is it dimmable" refers to the use of a phase-cut TRIAC dimmer in combination
with a retrofit LED bulb designed to run on mains power.

This combination does not work for all LED bulbs, because the electronics
in the bulb are trying to put a constant current through the LED independent
on the mains voltage, and now you are cutting down the mains power.
(not even the voltage, really)

You probably have a 13.8V stabilized DC supply in your shack.
Can you use it as a variable-voltage supply by putting a dimmer in
front of it?

No, not really. When you turn down the dimmer, the supply will first
try all it can do to keep the voltage at 13.8, and at some point it can
not achieve that anymore and the voltage will drop, but it will not
be stabilized anymore.

Similarly, a LED bulb may keep constant light emission for a large part
of the dimmer setpoint range, and at some point it goes down in intensity
in an erratic way.


We are just in the first phase of LED lighting deployment, the
"compatability" phase where the bulbs are still using existing form
factors of incandescent bulbs, and are supplied with mains voltage
that is converted to current inside the bulb. It is not the best
solution to use such bulbs in combination with existing dimmers.

Of course a next phase will be to use more reasonable form factors and
connection, where the electronics have a light level setpoint that
determines the LED current and the mains voltage is directly applied
without intermediate phase-cut dimmer.

On Fri, 28 Nov 2014, Jerry Stuckle wrote:

On 11/28/2014 4:11 PM, wrote:
In rec.radio.amateur.boatanchors Michael Black wrote:
On Fri, 28 Nov 2014, wrote:

In rec.radio.amateur.boatanchors gareth wrote:
These LED replacements for 240V mains lamps; if one were to
open them, would one find a high voltage regulator suitable for
some of our valve experiments and repairs?

As the regulators are potted in and would be difficult to remove, and
since LED's run on voltages on the order of 2-3 volts, no.

How many 3 volt valves can you name?

I think that point was that if a regulator was used to drop the line
voltage to those 3volts, it could handle high voltage input. The probably
false assumption is that the regulator would be variable from some very
high output voltage to some very low output voltage, so one could use it
for tubes by making that adjustment.

Given that manufacturers want the least cost in a product, and the
regulator in a light bulb would have no need for a variable regulator,
and that these things are made in the millions, it would be extremely
silly to assume that the regulator is anything other than a fixed
regulator for LED's and is designed to handle the load of some fixed
number of LED's.


Once again, incorrect. Have you ever heard of "dimmable LED bulbs"?
How do you dim without an adjustable regulator?

That may be semantics. LEDs are current driven, voltage won't have much
effect other than when fed through a resistor that does convert to
current.

More likely the LEDs would be driven with a square wave, and changing the
ratio of on to off would vary the light output of the LED.

Michael