[Amps] What tube?

[Larry]

AS far as I know, there is only one tube(s) that meet your requirements; 
a pair of 3-500Zs.

If you drop the "instant-on" requirement, there are quite a few other 
possibilities.

One other possibility if you can handle it might be 2X or 3X triode 
connected 4-400As. I've not been able to reliably get 1500 out on all 
the HF bands with a pair, but three in parallel makes it easy. See my 
web page for a 3 x 4-400A 40 meter monobander.

73,

Larry - W7IUV / WH2XGP


On 28-Jan-15 6:00 AM, Manfred Mornhinweg wrote:
> A question to all those of you who have used many different tubes:
>
> What tube(s) would you recommend for a legal limit HF amplifier, to get
> as close as possible to the following goals:
>
> - Class AB2 operation at high efficiency, low idling power, at
> acceptable IMD (doesn't need to be brilliant).
>
> - Ideally grounded grid triode, but a tetrode with screen supply is
> acceptable if a GG triode won't do it.
>
> - Instant-on filament, or at least quick heating (no more than 10 seconds).
>
> - Easy cooling requirements, so that a low noise fan or blower can be
> used. Maybe conduction cooled or water cooled.
>
> - Available and reasonably priced.
>
> I know I'm asking to much, but I would like to analize the best options
> out there!
>
> Manfred
>
> ========================
> Visit my hobby homepage!
> http://ludens.cl
> ========================
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>