Mt Diablo Amateur Radio Club (MDARC)

 Club Meeting

 

 Open to All!

 Join Us for Dinner and a Show!

 Grab your dinner and bring it to the meeting.

No Pacificon attendee badge is required

to attend this meeting.

 Friday Evening, Oct. 18, 2024

 7:00 PM

 Bishop Ranch, Salon E


Topic: Innovative Operational Op Amp Design

Ed Fong WB6IQN, edsantennas.weebly.com

We are now all familiar with then NanoVNA and the TinySA.  There are also numerous digital scopes now that are very affordable.  An example is the DSO03D12 -  a dual trace color portable oscilloscope with probes that easily measures in real time up to 150 MHz.  This instrument also has built in DVM and signal generator – all for less than $150.00.

These instruments would have cost in the thousands of dollars 10 years ago. Only the most serious hams own expensive HP or Tektronix equipment.  So why are they now all so affordable?  The answer can be summarized in one sentence -
innovative operational op amp design. (applications)

For the last 50 years, op amp design basically went unchanged.  Dave Fullagar designed the uA 741 in 1968. Unity Gain bandwidth -  1.5 MHz.  There were incremental improvements over the years.  Current mode feedback comes to mind.  However, these were evolutionary, not revolutionary.  With improvement in semiconductor processing, only incremental gains in frequency response was experienced - 10’s of MHz at best

However, back in the early 2000’s a new amplifier topology was invented.  This allowed controlled, high precision feedback gains in the 4-6 GHz range.  The rest is history.

Ed will explain this new topology in a non-mathematical format.  You will not find this configuration yet in many amplifier text books.