So. Here is how it works with no cap leakage.
E&OE.
Normal time constants do not work here as will be seen.


OPERATION:

Assume no cap leakage.

All off.
 C1! discharged,. C2 discharged.
 Power on.
 C1+, C2+ pulled high via LEDs by battery.
 As C1 and C2 have no V across them the -ve sides will also be pulled high.

 Bothe bases pulled high - boty transistors try to turn on.
 One will win.
 Say Q1 turning on faster:
 C2 will have some charge as -ve side discharged via base (or left side
chgd via R1 D1).
 QA Q1-c is driven to ground, C2- will be driven to BELOW ground.
 Q2 driven hard off
 If C2- driven more than about 0.6V below ground D4 conducts to clamp -ve
excursion.  Also provides a discharge path via Q1 - see below.
..
 Now Q1 on Q2 off.
 C1+ will charge via R2D2 (not a robot).
 Usually R4 is to B+ and it charges C2 so Q2 turns on.
 Q1 is on as above as C1 high but C1 is charging via R2 D2 C1 R3 so -ve end
falls until Q1 is not held on as Vb too low.
 But now C2 is discharged due to path Ground-D4-C2-Q1. So when Q1 turns off
Collector of C1 rises and lifts C2+ and so C2- follows so Q2 turns on and
identical second half cycle happens

This is a much damaged version of the original as usually bases are driven
negative and do not conduct during timing part of cycle and resistor
charges capacitor via a normal time constant. Here the caps forward bias
the bases when the opposite collector rises and you get massive base
current pulse via eg R1 D1 C2 Q2_base. So time constant of RC is much
shortened so oscillator will run rather faster than usually. T =3D RC of
bases is notionally 10k x 100 uf =3D 1 second but because capacitors are
clamped and discharged directly into bases this will run much faster.

So it works after a fashion but is crippled.




                      Russell
--=20
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