LED flasher circuit from Sprat 199

I tried the LED flasher circuit from Sprat 199:

Here is the waveform on the emitter:

It appears that the author, David G4COE, might have gotten the idea from one of these pages:

https://www.homemade-circuits.com/how-to-make-single-transistor-led/

http://cappels.org/dproj/simplest_LED_flasher/Simplest_LED_Flasher_Circuit.html

Here are some more links with information on transistor avalanche:

http://jlnlabs.online.fr/cnr/negosc.htm

https://web.archive.org/web/20190312005206/http://www.keelynet.com/zpe/negistor.htm

https://www.worldradiohistory.com/Archive-Poptronics/70s/1975/Poptronics-1975-12.pdf

http://www.kerrywong.com/2014/03/19/bjt-in-reverse-avalanche-mode/

I wasn't able to get the circuit to simulate using LTSpice.  The generic transistor models don't have the avalanche aspect incorporated.   BTW, this avalanche reverse breakdown is used with the Silicon Chip noise generator circuit mentioned here:

https://wb9kzy.blogspot.com/2023/12/noise.html

Bottom line: interesting circuit but it can't beat a blinking LED:

https://wb9kzy.blogspot.com/2023/07/blinking-led.html

Reasons:  more parts required for transistor circuit (5 versus 2) and high minimum required operating voltage (over 10 volts). 

More info on Sprat:
 
Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm