Anechoic Chambers

C-RAM FT-10 is a thin ceramic ferrite tile with exceptional RF absorbing characteristics in the frequency range of 30 MHz to 2 GHz.

C-RAM FT-10 is a sintered ceramic and is excellent for high power and high temperature application up to the Curie point of 203F. The tile has no outgassing and is ideal in high vacuum applications.

C-RAM FT-10 is frequently used in antenna caps and shielded enclosures to eliminate enclosure resonances during testing or emission measurements.

C-RAM FT-10 is used to line anechoic chambers for radiated emissions (ANSI C63.4) and immunity (IEC 1000-4-3) testing. These tiles can be combined with specially designed urethane foam pyramidal absorbers to extend chamber operation to above 20 GHz — see Technical Bulletin 390-6 for Hybrid Absorbers. Our engineers can help you with the design of anechoic chambers using either the tiles alone or in conjunction with hybrid absorbers.

C-RAM CFC is a series of high performance broadbanded RF absorbers designed for electronic and aerospace cleanroom applications. The carbon loaded foam is completely embedded in a clean material, so there is no dusting or release of conductive particles.

C-RAM CFC is made by embedding the corresponding grade of C-RAM SFC Pyramidal absorber in a mating section of low loss foam. The resulting box shaped absorber is then wrapped and sealed with an antistatic polyethylene film that can be wiped clean and requires no special vacuuming to maintain cleanroom conditions.

Because of the low dielectric constant of the foam insert, C-RAM CFC has essentially the same reflectivity as the SFC absorber it is made from, up through X-band. At millimeter frequencies, performance may begin to degrade slightly.

The Velcro Pile is factory installed on the absorber bases. The Velcro hook comes in ~25yd rolls with self adhesive backing. Peel off the release plastic sheet and press the adhesive side firmly against the wall. Metal wall surfaces should be free of oil film and dirt. A wipe down with denatured alcohol on a cloth will usually remove any oil film from modular shielding panels.If installing Velcro on raw wood we recommend giving the wood a coat of urethane varnish. The water based urethane products work well and are easy to use. You only need to treat the wood where the Velcro hook is to be attached.

We do not advocate using Velcro installation on absorber larger than 24” tall although 36” tall material have been installed using Velcro (3strips / piece on the walls and 4 strips / piece on the ceiling.

C-RAM SFC-HC is a series of high power pyramidal absorbers made from specially treated plastic honeycomb. Using a pyramidal design, which provides an impedance gradient, C-RAM SFC-HC provides premium performance in anechoic chambers at both normal and off-normal incidence angles.

Typically, C-RAM SFC-HC absorbers, with no forced air, can handle up to 10 W/in2 of RF energy with a phenolic coated honeycomb.

Cuming Microwave’s high power C-RAM SFC-HC has been fully tested at high power. A complete test report is available which shows W/in2 versus temperature rise in the honeycomb.

Several grades of C-RAM absorber materials can be supplied with a peel-and-stick pressure sensitive adhesive (PSA). This adhesive can be supplied to most grades of carbon loaded foam absorbers, such as C-RAM MT, as well as to many iron or ferrite loaded silicone and urethane rubber sheet materials, such as C-RAM GDSS, FLX, FLX-U, RGD-S, and FF-2.

This adhesive has been selected because of its high tackiness and strength at a very low thickness — 0.002 inches. This low thickness keeps the absorber material in close contact with the substrate material, allowing good attenuation of surface currents. For resonant grades of absorbers, such as C-RAM FLX, for which material thickness is critical, this adhesive has a minimal effect on frequency response.

We do not recommend using PSA on very heavy grades of iron or ferrite filled rubber sheets, such as those greater than 0.125 inches (3.2 mm).