Yes! Communication between tanks was often done either via a series of hand signals, signal flags or both. This would require of course the commander of a section to expose himself in potentially unfavorable conditions. The result is that early tank employment, especially in WWI, often had a very rigid plan and tanks operating in small units of pairs or sections of three; one reason was the simple lack of tanks in terms of how many were on the front, but also because commanding large formations in mass was a headache with early radio systems and hand-signals.

Its not just early tanks, either. Signal flags, hand signals, or quite literally climbing out of your tank to communicate remained relevant at least well into the late 1960s.

Why? Battle damage, wear and tear and even more frequently battle-confusion meant that units could get 'spread out' over several nets, here's the latest example I could find in my source books: A battalion commander whose companies get into what we call a 'knife-fight' with Syrian armor, 1967. At one point in the confused fighting, the entire brigade is on a single radio net, and at several points, he is only in contact via radio with a handful of tanks. Hand signals, signal flags and personal demonstrations ensue in an attempt to restore command and control. The entire situation is exacerbated by the emergency fighting and the hodge-podge of equipment that defined the IDF in this era:

Brigade signals wanted to talk to me. "I'm trying to get all the tanks in the area on your frequency. A unit has arrived with receivers of the old type - so we'll have to change your battalion wavelength" ...

"Shalom, hold on a few moments," I told the brigade signaller. Changing frequency now was a frightening prospect. Even a few seconds without contact might be a catastrophe, especially since there were too many tanks not on the frequency now."

As it became obvious throughout the line of Israeli tanks that communications were, indelicately put, FUBAR, more archaic communication methods are described:

There were heads sticking out of cuploas down the line, as tank commanders looked around for a leader. I tried to identify the battalion crews, than noticed that the tanks [which had been with a second company] were pulling back. I waved my arms frantically in attempt to find out why, but the commanders ignored me.

Not always with effect. When it became obvious that even hand signals (or in this case, frantic flailing) was failing to draw the attention of unbuttoned commanders, the Battalion commander moved on to leading by example:

Without any ability to issue commands, or check on implementation, the dense Syrian mass would bring us to a breaking point. There was only one thing to do.

"Policeman stations: Do not lose control over your neighbours, move forward to the ramps! Now!"

"[Company commander] here. Have two tanks with me. Am moving..."

I hoped that hand signals would do it. Meanwhile I went on calling...on the brigade frequency...

By appealing to his small-unit leaders who were on his radio frequency to move forward with him, the Battalion commander hoped units not in communication but within visual range of these officers would follow their example and fall in. This did not work the first few times, and the Israelis were forced to fall back from the lip of a ridge or risk being overwhelmed by dominating Syrian positions. A more successful attempt is made when:

I told [a platoon leader] to use flags to call the tanks around him up to the ramps. He straightened up in his turret and began to wave flags in both hands...

Other methods for gaining attention were also used:

Finally he fired a machinegun burst into the ground in front of [one of the tanks] - the commander swung around and took notice....

The section goes on at great length describing the teeth-gnashing efforts of the Battalion commander to get all his units back under command and control. I believe this sufficiently explains the myriad of methods that could be used to try and establish Command and Control in atypical situations. It was far from ideal, it was dangerous, but it could be done. However, in the author of this section's own words: It was no way to fight a war.

Source: Armor in Battle, US Armor School, 1986.