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Re: Tube Data
Hi All,
One of the main characteristics of an electron emission device
like a vacuum tube is that it will have a comparatively high output
impedance. The tube I mention below can supply 400ma at 5kV -
Z = V/I
Z = 5000/0.4
Z = 12500
This means that to avoid damaging the tube the load connected to it must
have an impeadance of at least 12.5 kiloOhms. Therefore it must use a
primary coil with a large inductance to provide this impedance.
For a typical disruptive TC operating at 300kHz with a 0.1µF primary
capacitor you would need about 28µH of primary inductance to tune, which has
an impedance of only 5 Ohms; whereas a vacuum tube design would use a much
larger primary to provide the large impedance, about 6.6mH would be needed.
This arrangement would suit a magnifier system as the large primary needed
could be wound co-axially with the secondary for most of its length giving
the very high K factor a magnifier needs.
Regards
Nick Field
> Original Poster: "Malcolm Watts" <malcolm.watts-at-wnp.ac.nz>
>
> Hi Nick (and others who have said such things in the past):
>
> > Original Poster: "Megavolt Nick" <tesla-at-fieldfamily.prontoserve.co.uk>
> >
> > Hi Guys,
> > thanks for all your help. I've eventually managed to get
the
> > data from an online database. Its a 2250W transmitter tube. The anode
> > dissipation is 500W, plate voltage 5kV, anode current 400mA.
> > I wonder if anyone has ever tried a tube driven magnifier?
> > To get the impeadance match right you'd need a large primary which would
> > suit the tight coupling of a magnifier driver.
>
> Could you expand on that last statement and perhaps throw some
> meaningful figures in for us to see please?
>
> Regards,
> Malcolm
>
>
>
>