Hello John,
W4MB had an article in Ham Radio a number of years back describing the
construction of a amp. with three 813s in grounded grid and I believe it
covered 40 thru 10 meters. If interested, let me know and I can dig up the
article and send you a copy.
73,
Mike, K4GMH
At 04:19 PM 2/11/98 EST, you wrote:
>> Is there experience here with using 813 in triode connection?
>
>Hello John,
>The 813 is a very rugged tube and has the reputation of being
>almost indestructable in amateur service. It is common to use it as
>a triode. The main limitation of the 813 in conventional circuits is
>reduced efficiency on bands above 20M.
>
>ZL1AXB has successfully used a circuit which tunes the filament
>and this improves the sfficiency dramatically. This tuned cathode
>network takes the form of a bifilar circuit, and eliminates the
>usual filament RF chokes. ZL1AXB demonstrates key-down >400W
>output on 10m with a single 813 with Pv of 3000v.
>
>The cathode circuit is described in an *Eimac* amateur service
>newsletter #AS-6 by W6SAI, W6KEV, and W6UOV. Some of the material
>may have appeared in QST August 1961 p16-21, but I have not checked
>this.
>
>Regards,
>Martin ZL1ANJ
>
>--
>FAQ on WWW: http://www.contesting.com/ampfaq.html
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>Search: http://www.contesting.com/km9p/search.htm
>
>
73,
Mike, K4GMH
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|