Re: tank circuit of VTTC

[FutureT-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

In a message dated 8/24/00 10:48:04 AM Pacific Daylight Time, 
tesla-at-pupman-dot-com writes:

> 1. In my records I found the 833 A to have a plate dissipation of 
>  300 W at natural cooling and a maximum plate voltage of 3000 V. 
>  Does the 833 C offer better data?

Herwig,

It seems that the 833C which has the graphite plates can withstand
considerably more power and abuse than the 833A's.  I have a few
"C's" but have yet to try them in a suitable TC.
>  
>  3. Plate voltage: Do you use a variac permanently and is your plate 
>  voltage 5 kV? Are there any arcovers *in* the tubes as the rated 
>  max voltage is 3 kV only?

I tend not to encounter 833A arc-overs until I reach about 5kVAC +
plate supply.  I've sometimes gone as high as 6kVAC.

>  6. In the schematic your tank coil is not tapped. How did you 
>  manage the tuning?

I often use both methods, and sometimes I just change the capacitance,
often using a large oil emersed variable capacitor for fine adjustment.

Cheers,
John Freau


>  Regards,
>  
>  Herwig