Re: Really big VTTCs

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Mddeming@xxxxxxx 

Hi Doc,

    There is a couple of RD-12-XH tube rated at 12 KW (15KV) on eBay 
right now. @~$200
each. One of the problems with mega-tubes for amateur use is that the 
filaments often require
supplies of 50-70 Amps each, and mounting hardware may cost as much 
as the tube. This
may not be a problem for you.
    Here is a family of such tubes. Many are in the Kilo-Dollar range.
Most of these are Russian-made:


Name TYPE POWER KW Max KV
RD4XM Triode 5.3 6
RD4XMF Triode 5.3 6
RD10XL Triode 20 8
RD12XH Triode 11 15
RD15VL Triode 40 10
RE15VM Tetrode 11 6.2
RD20XK Triode 30 11
RD30XM Triode 60 12
RD40XM Triode 60 12
RD50XL Triode 66 12
RD50XM Triode 50 15
RD70VL Triode 66 11
RD70VM Triode 66 11
RD250VM Triode 237 13
RD250VMV Triode 237 13

Hope this helps.
Matt D.


In a message dated 1/22/07 12:53:13 A.M. Eastern Standard Time, 
tesla@xxxxxxxxxx writes:
Original poster: "resonance" <resonance@xxxxxxxxxxxx>



I'm all ears.
|
Can you suggest a nice surplus tube that would handle 10 kVA at
around 7.2 kV?   I'm thinking of a small 7.2 kV, 10 kVA pole xmfr for
power.  Perhaps two big 10 kVA tubes running at 20 kVA into a 24 inch
dia. coilform approx 72 inches long.  34 x 8.5 inch toroid.  Perhaps
with John's stattaco controller on the tubes.


Regards,

Dr. Resonance

>By comparison, VTTCs seem to have topped out at a 4" x 20"
>secondary, driven by one to four 833A tubes.  The consensus seems to
>be that you can get just about as good performance from one 833A as
>with 4 of them, if you design the coil right.  Perhaps 36"
>discharges seem to be the limit for VTTCs on a good day.

>Is there some physical or electronic limitation to the design and
>construction of a really big VTTC?  With the availability of big
>surplus power tubes (10 kW or more) on eBay, and the possibility of
>multiple parallel free MOTs for input power, is there a physical
>reason why no one has built a 12 x 60 or 18 x 90 VTTC?
>Ten foot sword like discharges would be neat to watch!
>
>Dave
>
>
>
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