Questions, answered by the people who build them.

Yes — but start with the catalog. Any listed enclosure is a standard order, and that includes one with the I/O plate configured to the connectors you need: we build it and ship it in 3 to 4 days.

If nothing in our extensive stock is close to the size you need, we design the chamber to your dimensions. That's a fully custom build — 12 to 16 weeks. There's no middle tier: a listed enclosure ships in days, a custom chamber takes weeks.

We design fully custom test chambers from scratch when no existing design works. A ground-up design typically runs 12 to 16 weeks and carries a one-time non-recurring engineering (NRE) charge of roughly $3,500 to $4,500 to cover the design and tooling. Once the design exists, repeat orders follow standard lead times.

No. The configurations and interface options vary too widely to maintain a sample, loaner, or rental program, and we can't legally resell a previously purchased test chamber, so we don't offer returns on change-of-mind orders.

We do stand fully behind every purchase as meeting all specifications for its intended use. Because of this, the most important purchase decision is the mechanical size — getting a chamber that physically fits the devices you want to test. The connectors and filters can be changed later; the enclosure size can't. Before you order, we recommend reading the papers in our Resources section to specify the right chamber for your application.

Yes. The I/O plate used in most enclosures can be removed and sent back to us when a new test application needs different connectors. The enclosure can also be milled to add new options later. The field-changeable I/O plate is exactly why a JRE chamber doesn't become obsolete — you reconfigure the interface, not the chamber.

Yes. All of the hardware on our RF shielded test enclosures can be switched out in the field at your location.

Match the capacitance to your data rate. We stock filtered D-Sub connectors in a range of capacitance values:

• 1000 pF — up to 10 Mbps
• 100 pF — up to 100 Mbps

Pin counts vary by D-Sub manufacturer. Higher-capacitance filter networks give higher shielding effectiveness, so there's a trade-off between data rate and isolation — tell us your application and we'll help you pick. The Interface Connector Guide maps each connector and capacitance value to a signal type, and for rates beyond what a filtered D-Sub carries we build dedicated filtered interfaces such as USB and Ethernet.

It's a genuine conundrum, because high-speed data is a modulated RF signal — electrically and physically, the data and the RF you're trying to block are the same beast, so you can't simply filter one and pass the other.

For example, you can't filter the data lines on an RJ-45 LAN connector without capacitively loading them and destroying the link. At slow rates (around 10 Mbps), you can run a filtered DB-9 (100 pF is usually fine) with an RJ-45 adapter on each side — the filter attenuates RF while the slow data passes. Our filtered USB 2.0 uses a 1 GHz low-pass filter that passes high-speed data while stopping RF above 1 GHz; since most USB device testing is done at 2.4 GHz and up, that works well, though it gives minimal filtering at cellular frequencies (800–900 MHz).

For the fastest formats — USB 3, HDMI, and similar — John Ramsey's patented filter design separates the data cleanly even when interfering signals fall within the data passband.

Our guide Understanding Data Signals Through Filtered I/O walks through the three filtering approaches and when each one applies.

Yes. The capacitance in a filtered connector directly shapes the enclosure's RF isolation, so the data and power filters you choose affect overall shielding. Talk to our sales team and we'll determine the best option for your application.

It can. The connector body itself forms a tight RF seal, but the conductors passing through it carry no filtering unless the connector has feedthrough capacitors or similar built in. Any RF on that wiring can travel straight through to the inside of the enclosure — that's physics, and it's why we offer a wide range of filtered connectors, feedthrough capacitors, and dedicated USB data filters.

That said, mil connectors aren't hopeless. If your cable is well shielded, RF pickup tends to show up at the cable ends where the shield stops; with adequate precautions, the unfiltered connector can be usable. As a rough generality — a well-shielded, grounded cable longer than 4 to 5 feet, with no strong multi-watt RF sources nearby — you can expect around 60 dB of isolation, and many tests will work. We can't predict your exact result without knowing your physical setup, frequencies, and RF environment, so treat that as guidance rather than a guarantee.

Yes. Every vent option includes two ½" nickel-plated honeycomb-style panels tested to better than −115 dB shielding effectiveness at 1 GHz and better than −95 dB at 10 GHz. The honeycomb design is both rugged and effective, so you get airflow without breaking the shield.

Yes. Properly shielded cabling on RF bulkheads and data cables helps guarantee each enclosure's isolation. For best results, use double-shielded cable.

It's flatter than it needs to be. Our specs state a minimum isolation — for example, the JRE1724 is specified at a minimum of −100 dB at 1 GHz. If the actual isolation varies between, say, −107 dB and −123 dB across that range, it doesn't matter for most applications as long as it stays better than the −100 dB spec. If you genuinely need isolation at exact, specific frequencies, we can measure that for you at additional engineering cost.

At low frequencies, isolation approaches the −100 dB level published for each enclosure, with the actual figure dictated more by the I/O interfaces than by the box itself, because leakage at those frequencies comes from conducted emissions on cables crossing the shielding barrier.

One caveat from physics: an RF signal propagates via changing E and H fields. The enclosure effectively short-circuits the E field, which provides the isolation, but the magnetic (H) field is not shielded because the walls are non-magnetic aluminum. So for a magnetic-only signal — think transformer coupling between two nearby coils — you'll see limited isolation. Normal RF signals, like those from key fobs and similar devices, are highly shielded, beyond practical measurement at these low frequencies.

Our guide Using an RF Shielded Test Enclosure at Low RF Frequencies covers this in full.

Replace the gaskets after 20,000 lid cycles or once a year, whichever comes first. Replacement gasket kits are available for every JRE enclosure.

Industry practice is to measure field strength at 1 meter from the device, which keeps the measurement in the far-field region and avoids near-field errors. To verify isolation in the field, place a signal source such as our HPSS-1 inside the enclosure, "sniff" the outside at close range with a receiving antenna, then add a generous −20 dB path-loss factor to reference the close-in reading back to 1 meter (the real figure is typically around 30 dB at the HPSS-1's 2.45 GHz). Measuring directly at 1 meter is extremely hard, simply because the isolation of a JRE enclosure is so good.

Our guide Measuring and Verifying the Shielding Isolation of a Test Enclosure gives the full procedure.

On request, we provide a Certificate of Conformance with any enclosure. After manufacture we test every enclosure to confirm it meets its specified isolation, but we don't routinely log or document the individual measurements. If you need documented test results for your specific enclosure, we can do that at additional cost based on standard engineering billable time — tell us exactly what to measure and how, and we'll scope it.