[Amps] Operating a tetrode amp at very low power.

[Val]

Lukasz,

Running a 1500W linear amplifier at 50-100W out is not a good idea. I do 
not know your amp exact numbers, but if the plate voltage there is 3000V 
and the plate idling current is 300mA, the tube would dissipate almost 
1000W heat for 100W RF. Not much sense in wasting as much energy and an 
expensive tube's life time.

73, Val LZ1VB


On 23.01.25 18:35, Lukasz wrote:
> Hi,
> 
> In certain rigs/amps running at very low power level can result in much
> worse signal quality for various reasons.
> 
> Is this the case in tetrode (common cathode) amplifiers ?
> 
> Let me explain what I'm trying to do. I've recently got a SDR with
> transmit, but it puts out no more than few watts. This is perfect for my
> amplifier which requires 200mW (it has a two tube preamp, also tetrode,
> just tiny ones).
> 
> So I wonder, I don't always need 1500W, but <5W is definitely too little.
> I've built a switchable attenuator so I can easily drive the amp to achieve
> 100W or 50W. But I wonder if there is some hidden disadvantage to doing so?
> 
> 73, Łukasz - SP4IT
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps