Re: tube-noob question

No problem as long as they take the same current, i.e. 300 ma . If they take
different currents then you have to bridge the one taking less current with
a resistor so that the series current of the highest filament is equal.
Otherwise you'll burn out the filament with the lower current requirement

Ralph Cameron
"Ross, NS7F" <rjtucke@xxxxxxxxx> wrote in message
news:1181685604.458145.310470@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
In a circuit with two 6.3V tubes, can I just series the filaments so
that I can use a 12-13.8V supply? Or are there subtleties that I'm
missing?
Thanks,
Ross NS7F



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