Designed a traditional "Reflex Radio" by using LTspice (中学生 技術家庭科 レフレックス・ラジオ)

I designed a  traditional "Reflex Radio" by using LTspice.

I learned the radio so called "Reflex Radio" when I was a kid.

It worked well. It is very well-designed radio.

Fig.1 Reflex Radio (1BJT TR + 2 Diodes) for 9V work 

I tried to design it by using LTspice IV (developed by Linear Technology inc.).

The simulation is not always easy but I managed to design it.

It was proved this radio had very good performance even on LTspice.

Figure above is an example of successful work of the radio.

Fig.2 Reflex Radio (1BJT TR + 2 Diodes) for 1.5V work 

I tried to design the reflex radio which works using 1.5V battery.

It works OK with very low powered consumption.

Followings are failure examples of design.

---- > Output audio in the radio is unstable.

---> Abnormal oscillation occurs in this failed design. 

Following figure is an example of this reflex radio used in the education for junior high school student in 1977.

Copyright 1977 by the creator of the tutorial book. 

I found it by the Google image search. 

Noboru, Ji1NZL

---Revision---

0.1 May 24, 2016 Added a original schematic of the reflex radio.

0.2 Dec. 18, 2016 Added a new designed reflex radio for 1.5V battery work 

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