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Michael Black[_2_]

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