EMC Laboratory Time Savers Kimball Williams N C

EMC Laboratory Time Savers Kimball Williams N. C. E. k. williams@ieee. org U/M-Dearborn June 18, 2009

Quick Connect & Disconnect ‘N’ adapters Styrofoam blocks w/Rubber bands ‘No Mess’ LISN grounding

“N” Connectors l Problem: Ø Time to remove and attach “N” connectors in typical EMC measurement Systems. Ø Wear on connector and instruments threads in an “N” connector system.

¼ Turn – “N - C” Adaptors

Power meter ‘head’ calibration

Multi antenna test system

8 antennas is test system ¼ Turn Connector

¼ Turn Adaptors

“N” Push on / Pull off

Two Possible Solutions

Cautions l l l Rotating Assemblies – ‘back off’ Power transmission if not fully engaged Training so that co-ops do not disconnect equipment by removing the threaded portion of the rapid disconnector. Shipping equipment out for calibration with a fast disconnector in place (It won’t come back!) Questions?

Styrofoam Blocks • Problem: • Large Styrofoam blocks used for holding equipment under test and test harnesses. • Take up lots of space to store • Constantly being ‘broken’ or ‘eroded’ in use • Problems trying to ‘tape’ down the test harness

2” X 18” Styrofoam ¼” X 4” Wood Dowel – Cement 2” from ends. Rubber Bands

Test Cable

Styrofoam Blocks • Minimal use of Styrofoam materials • Fast Setup for Ground Plane test setup • Positive hold of harness on block • Easy to store materials when test is concluded • Questions?

Cautions l l l Harness or DUT may try to ‘walk’ the Styrofoam block on the table Some forms of Styrofoam may be subject to breakage and erosion Keep your stock of rubber bands hidden from secretarial help

“No Mess” LISN Grounding • Metal Tape Problems: • Sharp edges can cut technicians during application • Tape adhesive residue remains behind on ground plane • Difficulty achieving Resistance <2. 5 m. Ohms between LISN and ground plane • Tape is a ‘One Time’ use item and is expen$ive

LISN w/Tape Installation

Tape ‘residue’ on Ground Plane

Thumbscrew hold down method

Ground Stud pigtail Pigtail for ground stud

Bold Down LISN - Process • Clean both surfaces well (LISN base * Ground Plane) • Remove any cleaning residue with alcohol • Place the LISN / Gasket / Ground plane ‘sandwich’ parts together (Tuck in the Ground stud pig tail) • Apply hold down thumb screws and tighten ‘around’ the periphery of the LISN to bring fairly equal pressure on the gasket. • Measure resistance between the LISN base and the ground plane. (we normally get values around 650 u. Ohms with the first try.

LISN ‘Sandwich’ Pigtail to ground stud Home made ‘Gasket’ Brass Thumbscrews Wood Inserts

Questions? l Quick Connect & Disconnect ‘N’ adapters l Styrofoam blocks w/Rubber bands l ‘No Mess’ LISN grounding

Thank You!