John Byrns wrote:
> "Iain Churches" <IainNG@[EMAIL PROTECTED]
> wrote:
> > "John Byrns" <byrnsj@[EMAIL PROTECTED]
> wrote in message
> > > "Iain Churches" <IainNG@[EMAIL PROTECTED]
> wrote:
> > >
> > >> Can I suggest a topic for you? A current limiter for tube heaters.
> > >> People are keen to use voltage regulation, which doesn't seem to
> > >> me to be so im****tant. Heaters are specified at +/- 5% so
> > >> anything between 6V and 6V6 for a 6V3 heater is within tolerance,
> > >> and with a wirewound pot between two 'lytics one can get it spot
on.
> > >> But heaters draw huge currents at switch on. Do you have a
circuit,
> > >> using those funny black things with ****ny legs, that could current
> > >> limit? Two circuits would be of interest. One at say 1.2A
> > >> (a pair of B9A's) and one at 3A (a pair of EL34's)
>
> I forgot to ask, what is a "B9A", I can't find a listing for this tube
> type?
The B9A is a tube base style as used in ECC83s for example IIRC.
Graham
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