RS103 Test System Questions and Answers.docx

RS103 Test System Questions and Answers

1. The solicitation mentions that the existing MIL-STD-461 chamber walls and ceiling are lined with TDK Corporation IS-Series IS-030A and IS-045 radio frequency (RF) absorber materials. According to the datasheet for the IS-030A absorber the frequency range is specified from 800 MHz to 110 GHz, the IS-045 from 500 MHz to 110 GHz. Is this correct, since that will make it almost impossible to generate any meaningful field strength below 100 MHz. Even from 80 MHz to 500 MHz it will be very difficult. Is there data available of the absorber performance below 800 MHz for the IS-030A resp. below 500 MHz for the IS-045?

The TDK datasheet (001-02/20050615/e9e_bdj_003) for IS Material shows 6 dB absorption for IS-030A and 8 dB absorption for IS-045.

2. Which area of the chamber is lined with the IS-045 absorber? The solicitation only states “The IS-045 absorber is installed around the area where the ground plane is located in the ALSE”. Does that mean the first rows (if yes how many) on the walls have the IS-045 absorber?

The IS-045 absorber is located around the ground plane at the end of the EMI chamber opposite the doors. Reference the attached photo for details.

3. Where is the door into the ALSE located and what are the clear dimensions?

Reference the attached photo showing the placement of the door. The clear opening of the door is 7 ft. 0 in. by 8 ft. 0 in. W x H (2.13 m x 2.44 m).

4. Does the chamber have a raised floor?

No, the EMI chamber does not have a raised floor.

5. Where are the existing access panels located?

Two (2) 20 in. x 20 in. x 3/16 in. RF penetration panels are located on the same side of the EMI chamber as the doors. These are located on the EMI chamber walls on either side of the door opening.

6. Paragraph 4.2.2.1. Test frequencies specifies “The RS103 Test System shall be capable of generating the electromagnetic fields necessary to perform radiated susceptibility testing IAW MIL-STD-461G over the frequency range of 2 MHz to 18 GHz (T) 2 MHz to 40 GHz (O)”. However Attachment 0002 in the table Increment 2 specifies 1 MHz to 100 MHz. Which one is correct?

The conflict between paragraph 4.2.2.1 and 4.1.2 is noted. Paragraph 4.1.2 applies.

7. Paragraph 4.2.2.1. Test frequencies states “The RS103 Test System shall be capable of generating the electromagnetic fields necessary to perform radiated susceptibility testing IAW MIL-STD-461G at individual and multiple discrete frequencies under both manual and software control (T).” Please elaborate on “multiple discrete frequencies”, does that mean the system needs to be able to create a field at multiple frequencies at the same time? If yes, how many frequencies at the same time and at what frequency spacing?

The RS103 Test System does not need to transmit on multiple frequencies simultaneously. Recommend striking “at individual and multiple discrete” from the language of the solicitation.

8. Paragraph 4.2.4.2. Test antenna overall dimensions “The minimum distance between the transmit antenna and the test setup boundary shall be a distance of one (1) meter along a line perpendicular from the face of the antenna to the nearest face of the test setup boundary (T=O)”. Is a deviation from this allowed below 30 MHz since E-Field generators / antennas in 1 m distance generate almost no field. These generators specify the field typically between the elements.

A deviation to the minimum one (1) meter distance requirement is allowed at frequencies below 30 MHz. MIL-STD-461G Appendix A.5.21 RS103 Test procedures states “Test facilities are permitted to select appropriate electric field generating apparatus. Any electric field generating device such as antenna, long wire, TEM cell, reverberating chamber (using mode tuned techniques) or parallel strip line capable of generating the required electric field may be used. Above 30 MHz, both horizontally and vertically polarized fields must be generated. This requirement may limit the use of certain types of apparatus. Only vertically polarized measurements are required below 30 MHz due to the difficulty of orienting available test equipment for horizontal measurements.”