Leningrad+

[Maciej]

usually must be +5v but some pcb makers leave some pins in air. connect them to +5.
is+5 present at 13 pin of d11.4? , also - try use just cap - between scart and current video out from computer.

At 13 pin of d11 are +5V

try to take sync directly from 9pin D42.2 via capasitor 22mFx16v and res 1k to ground after cap.

it doesn't help

and check 2 transistors on the way from 9pin D42.2 to TV

I've took 2 transitors and build this section "on wire". Also didn't help.

i got idea - tell which same model of TV you use and how you connect Leningrad.

TV is CRT Nokia 37 A1(but i've tried on others). Connecton via SCART (RGB-15,11,7); at 16 pin +5V via 220R; 20 pin - sync.; 21(CASE) - GND.

looks like you havnt right ground btw. both devices - put gnd ( or - from 5v source) to antena shield pin.

Everything was connected

Да там дело не в этом, судя по скрину синхроимпульс просто отсутствует. Бланк есть а синхры нет. Я и посоветовал ему не мучить кошку, а просто заменить ТМ2 (74LS74) на новую.

Was replaced 2 times. No solution.

It seems that the reason is somewhere deeper