On Thu, June 14, 2018 3:09 pm, Dennis Monticelli wrote:
> Charles,
>
>
> I think I said that: "along with a series resistor to set the current."
> The more resistor drop the more current regulation. The current does not
> need to be perfectly constant. Having said that an LM317HV with a heat
> sink (probably need the HV version) is a better solution.
>
> Probably moot anyway. If direct radiation is the issue I think most hams
> would just get rid of the lamp and buy a recommended quiet one.
>
> Dennis AE6C
Problem is (at least in say LED flashlights, where I learned this from a
friend), the internal resistance is variable enough that using a current
limiting resistor makes it show a fairly high lumen output difference from
hot to cold, so just a current limit resistor was "problematic", but that
might be because at the time, we were driving the LEDs HARD, like right
near their max current, you know, like up near 3 amps! Thermal runaway
was a real issue
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