Thanks for the note. I agree that they might add more unwanted G-P capacitance. And I forget just how many hours I stared at those tubes wondering about that. :-)
Wide anode leads are used on many amps, and the purpose is to reduce the inductance of the leads, which in turn reduces the chances for VHF parasitic oscillations to occur. I think W8JI talks about that somewhere on his web site. Whether those wide copper strips helped or not, in the end I did not need a parasitic suppressor. And if you look at the photos, I took care to make each plate strap a different length, so as not to create a balanced push-pull circuit at VHF frequencies. Perhaps that was more important than the wide low-inductance anode conductors. They WERE made with the goal of removing heat and keeping the glass-to-metal seals cool, yes. As for heat sinks on the 833C anodes, I did extensive research on that. I found no commercial transmitter using one, nor any manufacturers' tube data sheet recommending a specific anode connector heat sink design than was any more elaborate than what I made. The 833 only needs forced-air cooling when run near its maximum ratings. There's a link to an old data sheet at the top of www.w0btu.com/833C_linear_amplifier.html and there are others on that web site (somewhere). I have no doubt that I could have done some things different. But it works great, and was a fun and inexpensive project. And I've ran it hard many times on 160 at the legal limit in CW contests. 73, Mike www.w0btu.com Mike, > > I was browsing your 833 amp pictures as a couple of those bottles sit on > my shelf. > > Could you explain the wide Cu straps on the plate? I don't know much > about tube amps, but would think with more area, they would make > neutralizing more difficult than the usual machined heat sink. _________________ Topband Reflector Archives - http://www.contesting.com/_topband
