Hello! This is not entirely my area of expertise, but I did study to be a professional musician in Russia, and this part of music history was also briefly taught to me, as well as explored by me and my peers in a somewhat professional manner (I mean, history of modern popular music in general is not as academic as many other flavors of history).

Electronic music in USSR had a strong pedigree. But it was a somewhat ambiguous affair: on one hand, USSR did have very prominent electronic musicians and musical engineers, who ultimately had a very far-reaching influence, both locally and to some extent globally. On the other hand, Soviet electronic scene, both academic and popular, remained comparatively insulated and provincial (for its potential), it wasn't a mass phenomenon until the very end of the era, and Soviet Union had few electronic bands and centers of active, organic development of electronic genres.

The history of influential Soviet electronic composers and engineers seems outside the scope of this answer, but it's important to at least go over it a bit. USSR did have a rather strong and unique school of synthesizer / electronic instrument designers (from Theremin's theremins to the photoelectronic ANS, a monster contraption that was essentially a no-limits sequencer that turns images into sounds), and a lineage of academic composers who heavily and successfully used these experimental synths — such as Denisov, Shnittke, or Artemiev (the latter very prolific in electronic film scores among other things, which confidently moves his music into the 'popular' dimension, heard by large numbers of people; prime examples are Solaris and Stalker).

The problem was, they were working with the ANS in the same single studio, the Moscow Experimental Studio for Electronic Music (МЭСЭМ, MESEM), which was subordinate to the state recording label Melodiya, which was in the purview of Ministry of Culture.

It helps to look at Soviet institutions as corporate ones: it's as if your country, a megacorporation, had a culture division; since it is understood that people need music, this division had a department of recorded music (e.g. Melodiya), and another department of concert music (e.g. Goskoncert). And these departments have subdepartments for genres, and local branch offices in different cities. Etc. etc. This department for recorded music, Melodiya, really did handle everything that has to do with recorded music: A&R, contracts, payments, production of recording media, pressing records and printing sleeves, distribution, marketing, retail stores...

...A "megalabel" if you will. And if this label decided that some type of music is needed, it was commissioned or musicians sought out who would produce it — just like regular record labels, but without alternatives. In that planned-out, officially approved lineup, experimental electronic music was a small afterthought — and hence did not develop much. Not persecuted, but not developed neither; stale, underfunded, and undermanned.

So that's the "serious" side of Soviet electronic music; the MESEM studio did ultimately put out one popular album, like a proof of concept that experimented with electronic music as widely accessible (featuring classical and modern pieces, a la Wendy Carlos' superpopular Switched on Bach in the West) — it was called Metamorphoses, was widely sold for years, and used to exhaustion in various screen media. But that's basically all from that side.

For a long time, something similar happened with pop-style electronic music. There was one big electronic orchestra in USSR, the Vyacheslav Mescherin's Ensemble of Electromusical Instruments — it worked as a "radio orchestra" and was on the balance of Gosteleradio, the state broadcasting corporation. It did put out very high quality electronic lounge / novelty / pop music and electronic covers of folk songs; several albums' worth of material. If measured in the traditional Western way, it was an epic success: hundreds of millions of people have listened to their music for years, on the radio, in dozens of movies and TV shows, as muzak. But this orchestra was, and remained, "unique" (read: the only really high-profile one of that type, because why have more?).

You see, it was understood that electronic music exists, and there was no specific stigma connected with it. But equally it was not something that the management regarded as especially needed in more amounts than necessary. Their logic, like with many other aspects of Soviet life, can be described so: "Do we have some electronic bands that can record some electronic music to put on the radio or TV, or do some crazy weird scores for motion pictures? Yes we do. Why have more electronic bands?"

And if you want to do electronic music, well, go study at a faculty of electronic instruments at a conservatory, then play in an existing orchestra of electronic instruments, or do film scores. Problem solved. Same on the listener's side: even if people would gobble up catchy electronic dance numbers instead of boring maudlin songs that dominate the TV, they will have to make do with what we produce and popularize. The percentage of, say, folk songs, crooner numbers, or classical pieces will remain the same (very high) regardless. Because the Party knows best.

Like any other genre of popular music in USSR, electronic or dance music had a specific, tame, conservative, safe, non-controversial version of it, that was approved for dissemination. Inside these stylistic boundaries (and inside the plan for how much music must be produced in a given time), people could establish a band and enter the circuit, write songs, record, tour, and so on. You just need to prove that that your music is wholesome and ideologically sound, and convince the management that this argument will hold water at any level (including the consumer level: an album or a concert would often be accompanied by an article or a lecture about how it's Socialist, useful, and progressive — unlike the regressive, morally bankrupt, and mercantile version of it in the West).

That is why even though free proliferation of "Western-type" rock or jazz music, countercultural at its core, was strictly banned and regarded as subversive and culturally degrading, — there were officially approved pop rock, lounge, folk rock, or light jazz bands and musicians, both recording/touring and simply playing at restaurants or dance halls.

And these musicians absolutely used electronic instruments — including proper synths. Soviet industry did produce a number of synthesizers that were supplied to music venues and bands. Some of them also see a resurgence now as strange artifacts from a parallel reality.

So what's the deal with Zodiac? First, a nuance: it wasn't from USSR. It hailed from Latvia. Warsaw Pact countries had their own flavors of everything Socialist, and sometimes were more permissive or more sophisticated in some respects. And this band, which is very relevant to the discussion above, was formed at the Latvian State Conservatory, by the students of the faculty of electronic instruments. They certainly didn't hide their genre roots: their first album was titled Disco Alliance.

But apparently the clean, wholesome, optimistic "spacey" version of disco (needless to say, space was the Soviet's jam!) was much preferable to the suspicious, chaotically diverse, and genuinely, actually subversive (even for the West) tenor of rock and punk. So Zodiac's music and local disco in general saw wide dissemination in USSR itself. Their music was used in movies and TV shows, and played at (approved, legal) discotheques.

This again meant in practical terms that if you, a person, wanted to make hip and modern music (and listened religiously to the formally banned foreign records available through the black market, like Zodiac members did), you could make your case to the culture authorities and establish an electronic band officially. Which was what Forum and Electroclub founders did. They toured through branches of Goskoncert, and recorded through Melodiya, like all others.

This of course coincided with general gradual liberalization of the 1980's; while it was in no way linear or consistent, many more things slowly became more approachable and less intimidating; and the growing new youth (counter)culture was growing directly inside the official infrastructure. Hell, most of the seminal Russian underground rock groups were established and supported via the entirely official Rock Clubs (Leningrad Rock Club (est. '81), Sverdlovsk Rock Club, and Moscow Rock Laboratory), which were created to legalize what people wanted to play and listen to, with grudging approval of older higher-ups. Underground music absolutely existed, but it often strived to legalize, since it would let artists do real concerts and press real records. And for electronic musicians, proverbial "apartment concerts" popular with Soviet rockers weren't really a desirable option.

Continued below.