Soldering cable ends for AC terminations

I always use solder.
1...It keeps loose strands of copper from shorting out.
2...It provides a "soft" metal to clamp down on, which I think improves the connection.

If the connection gets hot enough to melt solder you have made a really lousy connection!

Jea48...I have no problem with solder in audio equipment, but there is electronic equipment that uses another method which sounds unlikely but actually works very well. I am thinking of "wire wrap". The soft copper wire is twisted around a hard sharp-cornered pin, while under tension using a special tool. This method was used for thousands of connections in the electronics assembly of a missile inertial guidance system that I worked on. Very reliable, even under extreme vibration during missile flight, and unaffected by nearby nuclear explosions, where solder would be melted by X-rays.

Jea48...I doubt that the Russians did things much different from us. It would be quite impossible to implement anything but the most primitive guidance system using tubes. Our (US) late 1950's guidance system (Polaris Mk 1) was all solid state. Later, when radiation hardening became an issue, many features, most obviously, some shielding, were incorporated, but tubes were never considered. Many features of the hardware design, and the software which runs in it, have been developed to provide immunity to high levels of radiation.

There is one case where a tube was used in a recent design, and seriously considered for the most recent design. That is a Vidicon (optical imaging tube) used in space to sight on a star in order to correct for errors accumulated during the boost phase of flight. It was difficult to develop a CCD with the necessary radiation tolerance. Immunity to radiation was the only advantage of the vidicon.