PABX builder and telecommunications systems implementer National Telecommunications Plc, London E-based parent of National Telephones Ltd and National Telephones Systems Ltd plans to go public in a few weeks’ time with an offer for sale valuing the company at about UKP35m: the offer will be handled by Barclays de Zoete Wedd; National Telecommunications, also working on a voice messaging system for small businesses, expects to report sales for the year to March last of UKP20m, up from just UKP500,000 for 1984-85.