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2 GHz buffer with 2N390x

Started by Unknown February 23, 2020
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> writes:

> On 2020-02-24 16:36, Mikko OH2HVJ wrote: >> I've measured 30-300 MHz depending on mfg 1994-2015. Processes evolve and >> generic partnumbers, too. >> > > 30 MHz peak f_T for a 2N3904? > > 350-400 MHz at ~10-30 mA iirc.
Dang! - My measurments were not full characterization, but in-circuit with low I_c. So, not peak and I_c might explain most of the variation! Now that I've got the gear, I could do proper measurements if I can find some older ones. Thanks for spotting that out! -- mikko
On Monday, 24 February 2020 00:34:55 UTC, Michael Terrell  wrote:

> That reminds of of a guy with a brand new two year degree who believe that he could get 5W of RF at 27 MHz form a 2N3055. I gave him one. As I expected, he didn't even get a miliwatt output, which was as low as I could measure in my home shop at 17. He was like Sloman. He knew everything, yet he often needed help to repair a TV.
To be fair you can get 5w of 27MHZ out of a 3055... just feed 5w at 27MHz into all 3 terminals. 3055s were greased lightning compared to germanium power trans. NT
On Sunday, February 23, 2020 at 3:56:49 PM UTC-5, jla...@highlandsniptechnology.com wrote:
> https://www.allaboutcircuits.com/technical-articles/voltage-buffer-simulation-composite-amplifier-simulation-boost-output-current-drive/ > > > > -- > > John Larkin Highland Technology, Inc >
The article is not about the 2GHz buffer. A 200MHz buffer will work here too, that's why they don't care about it.