30-10-2017, 11:49 AM
I had cause to search for information on 'blocking oscillators' today and ended up at a Wikipedia entry : https://en.wikipedia.org/wiki/Blocking_oscillator
There was a link there to a web page at www.du.edu/~etuttle/electron/elect37.htm "by James B. Calvert. An elementary (no mathematics) and informative description of various blocking oscillator circuits, employing BJTs and Triodes."
Unfortunately that link now longer works but this one does : https://mysite.du.edu/~etuttle/electron/elecindx.htm , and partway down the index is #39, blocking oscillators. As it says, "Every circuit has been tested in the laboratory".
I got 'lost' in visiting many of the other entries on that index list, and it became a very interesting task although I was well and truly sidetracked by it all. Obviously the author is an amateur operator and several references to the ARRL Handbook are made.
Just as a matter of interest, I found that the root of the 'etuttle web' was actually at https://mysite.du.edu/~etuttle/ and it was designated as belonging to Dr Elizabeth R Tuttle so where the 'James B Calvert' comes into it is unclear. Note: Just found it..
"Composed by J. B. Calvert
Created 17 August 2001
Last revised 8 April 2003"
If you want to go adventuring and find out some interesting stuff on vacuum tubes (/ valves) as well as semiconductor use, be prepared to spend some time at this site.
73 Doug VK4ADC
PS Why I want a blocking oscillator circuit will remain undisclosed but have a look at the typical waveform generated..![[Image: cool.png]](http://ahrdf.net/forum/images/smilies/cool.png)
There was a link there to a web page at www.du.edu/~etuttle/electron/elect37.htm "by James B. Calvert. An elementary (no mathematics) and informative description of various blocking oscillator circuits, employing BJTs and Triodes."
Unfortunately that link now longer works but this one does : https://mysite.du.edu/~etuttle/electron/elecindx.htm , and partway down the index is #39, blocking oscillators. As it says, "Every circuit has been tested in the laboratory".
I got 'lost' in visiting many of the other entries on that index list, and it became a very interesting task although I was well and truly sidetracked by it all. Obviously the author is an amateur operator and several references to the ARRL Handbook are made.
Just as a matter of interest, I found that the root of the 'etuttle web' was actually at https://mysite.du.edu/~etuttle/ and it was designated as belonging to Dr Elizabeth R Tuttle so where the 'James B Calvert' comes into it is unclear. Note: Just found it..
"Composed by J. B. Calvert
Created 17 August 2001
Last revised 8 April 2003"
If you want to go adventuring and find out some interesting stuff on vacuum tubes (/ valves) as well as semiconductor use, be prepared to spend some time at this site.
73 Doug VK4ADC
PS Why I want a blocking oscillator circuit will remain undisclosed but have a look at the typical waveform generated..