When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
DJM Electronics AEP-4\" Pyramidal RF Absorber Foam – Professional Grade for Anechoic Chambers
Part Number: AEP-4Original Purchase: DJM Electronics, 2019Condition: Used for a short-duration project only – excellent condition, clean, and ready for immediate installation
Sold by the box. Each box contains eight (8) panels, each measuring 2 ft × 2 ft.Ten (10) boxes available (80 panels total / 320 sq ft of coverage).
Why These Absorbers Excel
These are genuine DJM Electronics (AEP Series) conventional pyramidal absorbers — the industry-standard material used in professional anechoic chambers, antenna test ranges, EMC facilities, radar cross-section measurements, and microwave research environments. Manufactured from carbon-loaded, fire-retardant polyurethane foam with a classic square-base pyramid geometry that creates a smooth impedance gradient from free space at the tips to highly lossy material at the base.
The 4-inch height makes the AEP-4 ideal for mid-to-high frequency applications where space is at a premium and outstanding absorption above 1 GHz is required.
RF Performance (Typical Absorption at Normal Incidence)
Performance scales strongly with frequency — this is classic broadband pyramidal behavior:
- 3 GHz: ~30 dB
- 6 GHz: ~35 dB
- 10 GHz: ~40 dB
- 15 GHz: ~45 dB
- 18 GHz and above (to 40 GHz): ~50 dB
Below ~1–3 GHz the absorption is more modest (as expected for a 4\" pyramid), which is why these panels are most commonly used for microwave and higher-frequency work or as complementary treatment in hybrid chambers. At higher frequencies the gradual taper delivers excellent return loss and very low reflectivity, making the chamber walls effectively “disappear” to the RF energy.
Power handling is typically rated around 0.5 W/in² continuous (approximately 0.775–1 kW/m² depending on exact conditions). Fire-retardant treatment meets NRL 8093 (Tests 1, 2 & 3) standards commonly required for chamber installations.
Physical Specifications
- Height: 4 inches (10.2 cm)
- Base size per panel: 24\" × 24\" (2 ft × 2 ft)
- Pyramids per panel: 144
- Lightweight and easy to handle / mount
- Classic blue color
History & Condition
Purchased new from DJM Electronics in 2019 and used only for a short-duration project. Panels have been stored carefully and remain in very good condition — clean tips and ready for professional installation. These are not “new-old-stock” from a warehouse; they are lightly used, high-quality production material. Note: Some panels have been broken into smaller pieces, but 2\'x2\' area and all 144 pyramids are present.
Ideal Applications
- Anechoic chambers (full or partial treatment)
- Antenna pattern measurement ranges
- EMC / EMI test environments
- Radar and microwave research
- Shielded rooms needing high-frequency absorption
- Educational or R&D facilities
Whether you’re building or upgrading a chamber, adding high-frequency treatment, or need reliable pyramidal absorber for a specific test setup, these AEP-4 panels deliver proven DJM performance at a fraction of new cost.
Quantity available: Sold by the box. Each box has 8 panels X $25 per panel = $200. (Less than half price of new!) Each box measures 25\" x 25\" x 25\" and weighs 20 pounds. A total of ten (10) boxes are available.
Local pickup preferred (heavy shipping volume), but shipping can be arranged for full boxes. Serious buyers — please contact with questions or to arrange inspection.
This is genuine professional-grade RF absorber, not generic acoustic foam. Ready to go to work in your next chamber or test facility.
