For sure, Ron, I've used passive input (swamping) on lots of amps, too.
The early ETO/Alpha amps, like my 374, has passive, swamped-input to a trio
of 8874's. The old National NCL-2000 was passive input and had to throw
away LOTS of power from the NCX-5 or whatever, since it only took ~20W to
drive it to 1 kW.
Those burned far more than 1dB...I think the NCL-2000 pad was about 6dB or
so, so it really did provide about a 4:1 improvement in impedance stability.
73 & drink more beer :)
Aloha
Steve WB2WIK/6
> This was from a very old W6SAI item. He intended it as a devise to reduce
> the power of your old tube, pi-network output exciter so you could load it
> up full as it should be to run clean and yet not overdrive your amp. He
> explained how to determine which T-PAD you needed to build, 1db, 2db, 3db
> or more, depending on how much power you needed to burn. It worked for me
> very well. I used it on a 3-1000, 2 single tube 4-1000's and a pair of
> 3-400's.
>
> Ron
>
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