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Good call! This should also reduce the driver tube's apparent drive power level. This is almost always a good thing. A single driver tube is a good match for 1960s radios that would bust a gut to dead key 3 and swing 11 or 12 Watts. And a tube-type CB final stage wouldn't care so much about the SWR.

More-recent radios routinely deliver twice, three or four times that drive level. My usual advice about linears with a single driver tube is to remove it and bypass the radio drive directly to the final stage. The resistor fix is probably a better bet than adding an impedance-matching circuit like you see in a D&A or later Palomar design. That would fix the high-SWR issue, but also have the effect of increasing the drive power to that single tube. Probably bad juju unless the radio is older than the amplifier.

73

[QUOTE="nomadradio, post: 846966, member: 22"] Good call! This should also reduce the driver tube's apparent drive power level. This is almost always a good thing. A single driver tube is a good match for 1960s radios that would bust a gut to dead key 3 and swing 11 or 12 Watts. And a tube-type CB final stage wouldn't care so much about the SWR. More-recent radios routinely deliver twice, three or four times that drive level. My usual advice about linears with a single driver tube is to remove it and bypass the radio drive directly to the final stage. The resistor fix is probably a better bet than adding an impedance-matching circuit like you see in a D&A or later Palomar design. That would fix the high-SWR issue, but also have the effect of increasing the drive power to that single tube. Probably bad juju unless the radio is older than the amplifier. 73 [/QUOTE]

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