[ARC5] Filament Power Sources

[Peter Gottlieb]

Be careful with those power supplies, many aren't RF hardened and go
ape crazy in high fields. I had a shack PC that smoked because RF got
in and the outputs went way high.


Peter

On Aug 24, 2013, at 12:59 PM, Ian Wilson <ianmwilson73 at gmail.com> wrote:

> I have blown a filament on a 4-125A when using a PC power supply. While
> a single case doesn't prove anything, this has never happened when using
> a transformer for filament power.
>
> I wonder whether the inductance of a real transformer acts to limit the
> starting transient, whereas a switching PSU is much stiffer and might stress
> a brittle filament on switchon. I am told that PC PSUs can be made somewhat
> soft-starting by adding a capacitor across the reference voltage resistor,
> but
> haven't tried it.
>
> 73, ian K3IMW
>
>
>
> On Sat, Aug 24, 2013 at 5:35 PM, Robert Eleazer <releazer at earthlink.net>wrote:
>
>> If you needed a lot of filament power at 6V, would there be anything wrong
>> with adjusting a 5VDC power supply up to 6V?  I have one of those that will
>> adjust up to 6V via a pot control and it'll put out 100 amps.
>>
>> Wayne
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