If you want to work on communication gear — especially in the 1960s — you probably wanted a VTVM (a vacuum tube voltmeter), a way to generate frequencies, and a way to measure frequencies and power. The Soviet military had a piece of portable gear that could do all of this, the IK-2, and [msylvain59] shows up how one looked on the outside and the inside in the video below. Be warned, though. The video is hard to stop watching and it runs for over an hour, so plan accordingly.
We don’t read Russian, but based on the video, it looks like the lefthand piece of gear is a frequency generator that runs from 20 to 52 MHz and a power meter. The right-hand instrument is a VTVM that has some way to measure frequency and the center section is a quartz crystal frequency standard.
The device has a battery, although there were problems with it in this unit. It can also take external power. Inside the portable case is a sturdy-looking pair of 100 ohm resistors in parallel to form a 50 ohm dummy load. The circuits inside are, as you’d expect, large surely hand-soldered components.
According to one of the comments, the unusual tubes inside were originally designed for Sputnik. While it is hard to imagine today, in the 1960s this instrument was a marvel of miniaturization.