And the baton goes to Zflyer48!
It's indeed the Su-15TM "Flagon-F", clearly identifyable from the perforated plate covering the top of the CRT display housing.
All of this belongs to the «Тайфун-М» (Taifun-M Radar, NATO code "Twin Scan"), which is the Flagon-F radar system.
Your turn Zflyer!
Cheers!
Mike