Technical Guidance Note 29

TOPIC: Masthead duplexers and amplifiers

ISSUE: 2

REVISION DATE: 27.1.98

PREVIOUS REVISION DATE: 6.9.95

BACKGROUND: In most EU member states (excluding Germany), masthead duplexers and amplifiers and their associated power units have been available in completely unscreened housings. In Germany, under VDE 0855 part 10, active antenna amplifiers mounted downstream from the antenna must be screened although it allows unscreened active indoor antennas (containing an amplifier). EN50083-2, reflects the above requirements of VDE 0855 part 10.

PROBLEM: Provided the manufacturer of the masthead amplifiers details the performance of the amplifiers to the customer (e.g. indicates unscreened nature of the product), can he continue to sell unscreened amplifiers onto the European market.

GUIDELINES: Since EN50083-2 is published in the Official Journal, such manufacturers have essentially three options:

Apply the EN50083-2.
Use a TCF to claim that the unscreened apparatus meets the protection requirements. If this involves placing a requirement for the end user to provide screening, then getting a favourable assessment for such a TCF would be difficult. Whilst it is possible to specify installation instructions required for conformance, specifying the overall screening of the apparatus is very different from specifying earthing or cable type requirements.
Don't sell unscreened amplifiers.

Disclaimer
No responsibility or liability can be accepted by the EMC Test Laboratories Association or any of its officers or members for the contents, specifications and/or advice referred to or contained in this Technical Memorandum and/or action taken as a result of information contained in this Technical Memorandum. Note that:
1. The Association is not by supplying this Technical Memorandum providing professional advice or guidance to any specific party on any specific matter and no legal relationship is created by the provision of this Technical Memorandum.
2. Parties should take specific advice when dealing with specific situations and consult their own professional advisors in this regard.
3. Members are free to deviate from the above guidelines where they think it appropriate, unworkable, or not commercially viable. Under these circumstances, the EMCTLA Secretariat should be informed of the reasons for the deviation so that the matter can be reviewed.