[ARC5] Filament Power Sources

[J. Forster]

Let me clarify that in my previous post, I was referring to quality
computer power supplies, NOT something out of a PC, like the TDK/Lambda or
other maker's 'bricks'.

-John

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


> 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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