2 GHz buffer with 2N390x

[Mikko OH2HVJ]

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.