>At one time, before the GPS satellites made them redundant, there was a
>string of Loran stations along the Atlantic coast of Canada.
>
>The workhorse at these stations was a linear, using a pair of 4CX350's,
>built by Technical Material Corporation of Mamaroneck, NY and Ottawa,
>Canada. The Loran is gone, but the linears are still around,
>beautifully-built units, good from 2-32mhz, ideal for ham use.
>
>Well, not exactly. These linears can be driven to full output with only
>a few watts of drive into the exciter stage (which uses a 6CL6 and a
>6146).
>
>So I removed the exciter stage, and converted the 4CX350's to grounded
>grid, reasoning that now the linear can be cathode-driven directly by my
>Yaesu FT-900, which has an automatic antenna tuner.
>
>That's where I'm at, and my question for the experts is: what kind of
>matching network at the cathodes of the 4CX-350's is recommended??
>
** G-G operation for the 4cx350 is seemingly risky due to the delicacy
of the grids. The 4cx350 was designed for AB1, grid-driven service. If
I were building such an amplifier, I would terminate the grid with
12.5-ohms, and drive the grid through a bifilar 4 to 1 step-down
torroidal transformer
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