Ten Japanese and European manufacturers of videocassette recorders said they plan to develop a common set of specifications for next-generation, high-definition digital VCRs.The move follows earlier agreements between the firms, led by Matsushita Electric Industrial Co. and Sony Corp. as well as Thomson Consumer Electronics and Philips Electronics N.V., regarding basic digital VCR technology. The 10 firms said in a statement that they will form a “technical conference” in September to decide on high-definition specifications for the units. The conference will be open to industry participation and will offer information on basic digital VCR standards. The 10-company group includes Hitachi Ltd., Mitsubishi Electric Corp., Sanyo Electric Co., Sharp Corp., Toshiba Corp. and Victor Co. of Japan (JVC). The group said the conference would submit its resultant high-definition digital VCR specifications to the Intl. Electrotechnical Commission, with the aim of establishing a world standard.