From 1981: the first issue of British Gerry Anderson fan magazine SUPERMARIONATION IS GO!
I think I have posted this launch issue before but I recently acquired another copy (duplicates are an occupational hazard) and was pleased to see that this copy still included the original welcome letter from Gerry himself tucked inside. So well worth a repost.
I don't think this was originally conceived as Fanderson's main publication but it was soon adopted as such when the various branches of Andrson fandom were encouraged to cooperate more closely by Gerry himself and copyright holders ITC.
In a move that was probably beneficial to the magazine but counter-productive to the club, copies were also carried in specialist stores courtesy of Titan Distributors. Thereby eliminating any particular need for casual readers to enroll. The modern version of Fanderson doesn't repeat that mistake, restricting both the newsletter and merchandise to members only.
The title switched to the less unwieldy S.I.G IS GO! from the fourth issue (Spring 1982). Colour covers were introduced a year later (Spring '83) and the increasingly professional publication eventually ran to twenty issues (Autumn 1988).
It was published alongside the equally excellent TIMESCREEN which was dedicated to a wider range of British Telefantasy shows.