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Just install different tube socket for an available tube. If want solid state you pretty much will have to gut the old tube amp so why bother might as well just build what you want and toss it in a project box. I would not waste my time with old bipolar designs like the 2879 unless you have a lot of them on hand. Let be clear for a base station amp. I would go LDMOS and either go with 110 or 220V. Then you are not having to step up or step down power from mains. You would then just be regulating and cleaning up the power mostly to make sure you did not draw more current than your wall socket can supply and to clean up the dirty electricity most of us int he USA have supplied to our homes. If you choose wisely you can find LDMOS that can work from 50V to about 500V depending on what you choose. The latest stuff designed for RF has crazy insane SWR rating both loaded and unloaded. They have really high multiplication factor or gain so long as the voltage is not low. So you can realistically get 1200-5000 watts with an input drive of 100watts. The really good stuff is high voltage and high amperage so the only limiting factor at home is the wiring inside your walls and going to the power poll and the breaker ratings. Most home circuits in America vary between 16 and 45 amps of current rating in all the places I have lived with 25-30amps being the norm. I am not an Electrician so my observations really only apply to me. If you are already set up for 220V I would consider going that way as well. I have 220 in my garage so it would not be hard to brin 220 into the rest of my home. If I had large enough tube amps I would consider 220V as well.

I have some LDMOS transistors sitting around but I have about 8 bipolar PCB boards I need to build before I play around with my LDMOS.

You could prob. use most of those parts inside that amp to build a single tube unit with a Russian GI-7BT tube. Might need a different diode board like one from a Heath Kit SSB-220 or the like.

<blockquote data-quote="Onelasttime" data-source="post: 576003" data-attributes="member: 21190">Just install different tube socket for an available tube. If want solid state you pretty much will have to gut the old tube amp so why bother might as well just build what you want and toss it in a project box. I would not waste my time with old bipolar designs like the 2879 unless you have a lot of them on hand. Let be clear for a base station amp. I would go LDMOS and either go with 110 or 220V. Then you are not having to step up or step down power from mains. You would then just be regulating and cleaning up the power mostly to make sure you did not draw more current than your wall socket can supply and to clean up the dirty electricity most of us int he USA have supplied to our homes. If you choose wisely you can find LDMOS that can work from 50V to about 500V depending on what you choose. The latest stuff designed for RF has crazy insane SWR rating both loaded and unloaded. They have really high multiplication factor or gain so long as the voltage is not low. So you can realistically get 1200-5000 watts with an input drive of 100watts. The really good stuff is high voltage and high amperage so the only limiting factor at home is the wiring inside your walls and going to the power poll and the breaker ratings. Most home circuits in America vary between 16 and 45 amps of current rating in all the places I have lived with 25-30amps being the norm. I am not an Electrician so my observations really only apply to me. If you are already set up for 220V I would consider going that way as well. I have 220 in my garage so it would not be hard to brin 220 into the rest of my home. If I had large enough tube amps I would consider 220V as well. I have some LDMOS transistors sitting around but I have about 8 bipolar PCB boards I need to build before I play around with my LDMOS. You could prob. use most of those parts inside that amp to build a single tube unit with a Russian GI-7BT tube. Might need a different diode board like one from a Heath Kit SSB-220 or the like.</blockquote>

[QUOTE="Onelasttime, post: 576003, member: 21190"] Just install different tube socket for an available tube. If want solid state you pretty much will have to gut the old tube amp so why bother might as well just build what you want and toss it in a project box. I would not waste my time with old bipolar designs like the 2879 unless you have a lot of them on hand. Let be clear for a base station amp. I would go LDMOS and either go with 110 or 220V. Then you are not having to step up or step down power from mains. You would then just be regulating and cleaning up the power mostly to make sure you did not draw more current than your wall socket can supply and to clean up the dirty electricity most of us int he USA have supplied to our homes. If you choose wisely you can find LDMOS that can work from 50V to about 500V depending on what you choose. The latest stuff designed for RF has crazy insane SWR rating both loaded and unloaded. They have really high multiplication factor or gain so long as the voltage is not low. So you can realistically get 1200-5000 watts with an input drive of 100watts. The really good stuff is high voltage and high amperage so the only limiting factor at home is the wiring inside your walls and going to the power poll and the breaker ratings. Most home circuits in America vary between 16 and 45 amps of current rating in all the places I have lived with 25-30amps being the norm. I am not an Electrician so my observations really only apply to me. If you are already set up for 220V I would consider going that way as well. I have 220 in my garage so it would not be hard to brin 220 into the rest of my home. If I had large enough tube amps I would consider 220V as well. I have some LDMOS transistors sitting around but I have about 8 bipolar PCB boards I need to build before I play around with my LDMOS. You could prob. use most of those parts inside that amp to build a single tube unit with a Russian GI-7BT tube. Might need a different diode board like one from a Heath Kit SSB-220 or the like. [/QUOTE]

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