4-1000 A tube Bandit Box

[@LarryYaw]

100 in gives me 1900 out. I have built 2 of them. Do you have a tuned input? I run mine on the ham bands.

[@luckydubeinrc5165]

yeah thats about right at 4kv they need lots of drive being a Tetrode , at 6kv they push a bit more than 2700 watts , but that is maxxed. i would suggest the next one :) move the variable closer, maybe un top of the other, for shorter lead length and less stray capacitance, but over all it's a homebrew so we make do with what we have .

[@tbirdslot69]

Was there any adjustable input tune in the amp

[@grannyfisher3863]

No.

[@tbirdslot69]

@@grannyfisher3863 a friend in NW Arkansas has it now and says input reflect is extremely high using a 100 watt radio. Just trying to get info for him

[@crashland73]

I am the one who has this now. Im using a kenwood ts-440s radio to run it. But im only getting 600w out of this. Is it because im only using a 100w radio to push it? Thank you.

[@grannyfisher3863]

That particular tube and amp takes a lot of drive. Do you have a new tube in it? I was seeing legal limit with that. My guess is the tube is old. What frequency are you using it on?

[@crashland73]

Im on a local normal meter. On my particular radio it shows channel 38 mainly. Tonight i tried a killer bee 250 set at 150 & 200w & still caint get above 7-800 watts. I dont know which knob does what so im doing the best i can. Is there any way i can call you & talk rather than here? If not its all good, its just that this is my first tube type anything. My 1st was a varmint xl1000. I went with yours because of my kenwood pushing 100w. Ive been dialing the left big knob to peak & the right knob the same. Then back the left knob down to have swing. The tiney knob i turn full blast. I live “near” harrison ark. Do you by chance have a better main tube? Sorry for all these questions. Im a tube beginner.

[@crashland73]

Any way you can lead me in the right direction here sir?

[@grannyfisher3863]

@@crashland73 That tiny knob is for filament voltage and you do not need to turn it wide open. Turn it to 6 volts, and my guess you bought this from Fluffy Duck, and it still has the same tube in it that Fluffy was running. If so, you need a new 4-1000 tube. Your tuning to peak and everything is fine.

[@crashland73]

I do no know that particular handle. The guy i got it from may have. He hiself has had it about a year. Do you by chance have one of these tubes for it? Thank you.

[@MM0IMC]

Do you have any problems with that long brass strap going from the tank coil, to the variable capacitor?

[@grannyfisher3863]

He said, "I did, but I put that blocking capacitor at the end of it. That amp was in use for about 3 years before a guy blew it up overdriving it. He was putting about 400-500 watts into it."