Amplifier Drive Input... 5w / 10w / 50w?

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  • Updated 4 months ago
Hey all, is there a recommended or preferred drive input for an amplifier connected to a Flex-6600? I'm considering a new 1K amp and some amps have the ability to specify drive input? 
Photo of Dwayne - NA6US

Dwayne - NA6US

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Posted 4 months ago

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Photo of KF4HR


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Each amp will have different drive requirements, and drive requirements will also differ slightly per band too.  Check the amp's manual to determine its input power range. 
Photo of William Osborne

William Osborne

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Dwayne, I have an SPE 2K and the SPE amps lets you control the drive level from the Flex if you connect them via CAT.  Mine varies from about 32 to 40 watts for 1,500 out and somewhat less for 1,000 out.
Photo of Pat N6PAT


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It all depends on the amp. I have one amp that requires just 3 watts drive for 300 watts out and another amp that requires almost 50 watts drive ( which would completely fry the first amp ) to get the same 300 watts out

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Rob N4GA

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Nobody has answered your question. 

I assume the FLEX is the cleanest at just under full power, like maybe 80-90w, since its output transformer has been likely designed and compensated around this power level.

But only FLEX knows for sure. Whatever level it operates the cleanest would be the ideal input power to your linear.


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Rick Hadley - W0FG

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At the Mid-power level (1K), which is where I usually run it, my SPE 1.3-K only requires 6-7 watts.  Anything over that is overdriving it. On most bands, for 1.5K, it's 10-11w.

Rick, W0FG
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Neal - K3NC, Elmer

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My RF Kit B26 2K+ takes about 10-15 watts for 160-10 (minus 30m where we can go 1500w!) I haven't really tried it on 6m but I hear it can take as much as 60w to get 500w out. But each model of amp (and probably each sample within a model) can take different power.