Hi All,
I havent been around here in quite a while, been hanging out at the CBT forum when time permitted, which hasnt been much!
Im getting back into doing projects and i recently scored an old beat up kris power pump linear amp.
it was cheap enough that it was worth it for the parts.
i have a thread going over at the other forum, but there's not much traffic over there, so i thought i'd start one over here so others can get in on the discussion.
this is my first tube amp build and im learning a lot about how these things tick.
yes, its a sweep tube amp. yes, the tubes are obsolete, expensive, and not meant for what they are doing...
we all know all of that already so please dont turn this thread into a debate about the merits of sweep tube amps.
the upgrades i am doing so far are:
1. adding parasitic suppressors. (lots of debate about this but i figured it cant hurt)
2. removing the driver tube and converting the amp to a straight three tube amp.
3. adding an input tuning network
4. i am adding 10 ohm resistors in series with the feeds to the cathodes as suggested in an ARRL article about sweep tube amps. its supposed to enhance the linearity.
5. i am adding bias to the control grid on pins 2 and 6 so the amp will be class AB1.
here are a few pics and there is a hand drawn schematic i made that shows the upgrades. its a PDF file.
PS- i forgot to mention my great appreciation to nomadradio who has been helping me along the way.
I havent been around here in quite a while, been hanging out at the CBT forum when time permitted, which hasnt been much!
Im getting back into doing projects and i recently scored an old beat up kris power pump linear amp.
it was cheap enough that it was worth it for the parts.
i have a thread going over at the other forum, but there's not much traffic over there, so i thought i'd start one over here so others can get in on the discussion.
this is my first tube amp build and im learning a lot about how these things tick.
yes, its a sweep tube amp. yes, the tubes are obsolete, expensive, and not meant for what they are doing...
we all know all of that already so please dont turn this thread into a debate about the merits of sweep tube amps.
the upgrades i am doing so far are:
1. adding parasitic suppressors. (lots of debate about this but i figured it cant hurt)
2. removing the driver tube and converting the amp to a straight three tube amp.
3. adding an input tuning network
4. i am adding 10 ohm resistors in series with the feeds to the cathodes as suggested in an ARRL article about sweep tube amps. its supposed to enhance the linearity.
5. i am adding bias to the control grid on pins 2 and 6 so the amp will be class AB1.
here are a few pics and there is a hand drawn schematic i made that shows the upgrades. its a PDF file.
PS- i forgot to mention my great appreciation to nomadradio who has been helping me along the way.
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