Regimes on the direct current (DC), relative to the common wire: 
supply voltage by 8,8 
voltage of supply of preamplifier 8,6 
base of first transistor 0,7 
emitter of first transistor 0,16 
resistor 47 Ohm 0,018 
collector of first transistor 7,2 
base of second transistor 2,4 
emitter of second transistor 1,8 
collector of second transistor 8,5 
voltage on diode 0,67 
resistor 2,2 Ohm 0,067 
collectors of output transistors 8,7

Transformer 1:
input: R = 41 Ohm; L = 0,51 H; Q = 1,36
output: R = 49 Ohm; L = 0,53 H; Q = 1,39
the halves of outputs are identical
core 7mm * 5,5mm = 38,5 mm^2

Transformer 2:
input: R = 7,5 Ohm; L = 54,5 mH; Q = 2,1
the halves of input are identical
the halves of output are not identical
output 1 (lower according to diagram): R = 1,1 Ohm; L = 8,5 mH; Q = 2,45
output 2 (upper according to diagram): R = 0,4 Ohm; L = 0,47 mH; Q = 2,6
core 11mm * 7mm = 77 mm^2

AC signal (peak to peak) :
input signal : 200 Hz, injected sine signal 4mV, vol pot set to 1/4, 
T1 input (base) : < 1mV
T2 input (base) : 6mV
T2 output (collector) : 48mV
Tr1 output : 2 x 16mV
Tr2 input : 2 x 260mV
+HP input : 180mV
feedback signal (before 68K res) : 220mV