Re: 811A any good?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Mddeming-at-aol-dot-com>

In a message dated 1/23/01 10:43:44 AM Eastern Standard Time, 
tesla-at-pupman-dot-com writes: 




>
> Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" < 
> Parpp807-at-aol-dot-com> 
>
> In a message dated 1/22/01 10:12:55 PM Central Standard Time, 
> tesla-at-pupman-dot-com writes: 
>
> there was a schematic using a 811A tube to drive a VTTC, on some 
> > website which I can't remember or find. 
> > 
> > Anyway, is a single 811A tube any good for a table top VTTC? 
> > 
> > Just asking because it is so cheap, about $25 per piece from 
> > www.elfa.se ... 
> > But those ~250W seem very little? 
> > 
> > - Jan   
>
> << Hi Jan! 
>       The 250 W is about the point where the plate starts to show a dull 
> red 
> glow. If you can get a copy of the RCA technical manual TT-5 "Transmitting 
> Tubes - to 4KW Plate Input" it has all the specs. Reprints are available 
> from 
> Antique Electronic Supply of Tempe Ariz. 
>
> Matt D.    >> 
>
> Hi Matt, 
> The 811 is a great tube for a VTTC but you guys better take another look at 
> the 
> TT-5 and the 811 specs. The max plate dissipation is around 60 Watts. The 
> 811 
> is just a big 807. They make great triode PP stereos. :) 
>
> Cheers, 
> Ralph Zekelman 



Ralph, Jan, et. al. 

Your right that the average power rating for the 811A is "45W CCS and 65W ICS 
averaged over any audio-frequency cycle of sine-wave form". Maximum plate 
input (pulse peak) is in the range of 230-260 Watts (radar-type 
applications). It's usability depends critically on the type of circuit and 
the type of signal. 

Matt D.