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Just because you don't see a bias circuit on a tube amp does not suggest it can't be used on SSB or that the tubes will operate in class C as a transistor amp would without bias. Many tubes can be run with "zero bias" voltage and still run class AB1. If the plate voltage is not too high, the tubes will draw close to the correct idling current. Remember with most tubes the bias circuit is used to reduce bias current since maximum idling current would be achieved with zero bias. Also, as was mentioned this amp will have a 100 ohm input impedance with a pair of tubes. That's a 2:1 input VSWR. Most transistor rigs won't like this without a tuner.

[QUOTE="Shockwave, post: 422597, member: 10882"] Just because you don't see a bias circuit on a tube amp does not suggest it can't be used on SSB or that the tubes will operate in class C as a transistor amp would without bias. Many tubes can be run with "zero bias" voltage and still run class AB1. If the plate voltage is not too high, the tubes will draw close to the correct idling current. Remember with most tubes the bias circuit is used to reduce bias current since maximum idling current would be achieved with zero bias. Also, as was mentioned this amp will have a 100 ohm input impedance with a pair of tubes. That's a 2:1 input VSWR. Most transistor rigs won't like this without a tuner. [/QUOTE]

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