Skip to content
Start a spec →

Application guide

Slip rings for radar & antenna positioners

A rotating radar antenna needs high-power RF in and out, plus power, encoder signals and data, all running 24/7 for decades. RF channels go through waveguide or coaxial rotary joints that use non-contacting chokes, while the slip ring around them handles everything else. Multiple radars (primary, secondary, IFF) often share one stack, so channel isolation and stable RF performance during rotation are critical.

Configure for this application →Ask an engineer
Slip ring

UK engineering team · Product sourcing · Supply support

Tell us what the slip ring needs to do

Send your part number or describe what the machine needs to do. We connect your requirement with experienced UK engineering and procurement support to help you get the right products, pricing and supply options. Your matched provider can take the enquiry through quotation and ordering to delivery and after-sales support.

  • Source original parts or assess suitable alternatives
  • Get pricing, lead times and a defined supply proposal
  • One enquiry for components, complete axes and ongoing support

No obligation to buy. Choose the quick form below or use the full configurator on this page. Add what you know; an engineer can help with the details.

Need help choosing? Build a specification →
Add quantity, timing or application notes (optional)

Spec builder

Configure a slip ring for radar & antenna positioners

Select the products and performance you need. Our UK engineering team can use your specification to help source the right components, pricing and supply options. See your summary before adding contact details.

Already know the part number? Use the quick enquiry form. You can configure a requirement below without registering.

  1. 1Products
  2. 2Performance
  3. 3Environment
  4. 4Volumes
  5. 5Your spec
Step 1 of 5

What are you specifying?

Select everything you need. A motor, drive and gearbox can be specified together as one axis.

1 selected: Slip ring

What the slip ring has to handle

  • Multi-channel RF rotary joint (waveguide and/or coax) stacked with an electrical slip ring
  • RF power handling from hundreds of watts up to megawatt peak in L- and S-band air-traffic radars
  • Slip ring ways for antenna electronics, heaters, encoders and data (typically 5 to around 40 ways)
  • Optional fibre optic channels for digitised radar data
  • Continuous rotation, commonly around 15-60 rpm, with life measured in tens of millions of revolutions
  • Wide temperature range and high humidity tolerance for exposed pedestals
  • Shock, vibration and EMC qualification for military platforms

Typical figures

Speed60 rpm typical for ATC rotary joints; one 6-channel unit rated 15 rpm; military COTS ring tests at 250 rpm
Rf powerATC rotary joints from 5 W peak to 1.5 MW peak; average up to 11 kW
Rf channelsUp to 9 RF channels
Slip ring ways5 to 38 ways integrated in ATC rotary joints
Life20-50 million revolutions minimum
Temperature-55 C to +85 C range across ATC models; military COTS rings -40 C to +80 C
Ingress protectionIP40 to IP66 (rotating part)
Vibration shockMilitary COTS test: random vibration 20-2000 Hz at up to 12 g rms; shock 20 g, 11 ms

Example figures from the published sources listed below. Your requirement may differ; an engineer will confirm against your duty cycle.

Recommended slip ring types

Through-bore slip ringsLarge-diameter slip ringsFibre optic rotary jointsRugged and military slip ringsHigh-speed slip rings

Standards to consider

  • MIL-STD-810 - environmental test methods (vibration, shock, temperature) for military radar hardware
  • MIL-STD-461 - EMC requirements for military equipment and subsystems
  • IEC 60529 - IP code for pedestal enclosures

The complete system

A slip ring rarely works alone. For radar & antenna positioners it is usually specified together with:

  • waveguide or coax RF rotary joint
  • azimuth drive motor
  • servo drive
  • absolute encoder
  • slewing bearing
  • gearbox
  • brake

Specifying these together avoids mismatched connectors, cable routes and feedback interfaces, and gives you one point of contact for the whole axis.

Common problems to design out

  • VSWR or insertion-loss variation with rotation (wow) on RF channels
  • Brush and ring wear after tens of millions of revolutions
  • Moisture ingress and corrosion on exposed pedestals
  • Crosstalk between RF, data and power paths

Series used in this application

Motion Control Products PR/PSR Series Pancake Slip Ring

Frequently asked questions

What is the difference between a slip ring and an RF rotary joint?

An RF rotary joint carries microwave signals using waveguide or coax with non-contacting quarter-wave chokes. A slip ring uses sliding contacts for power and lower-frequency signals. Radar pedestals usually stack both in one assembly.

How long do radar rotary joints last?

Air-traffic-control rotary joints are typically specified for 20 to 50 million revolutions minimum at around 60 rpm. Life is driven by total revolutions, environment and sealing.

Can fibre optics pass through a radar rotary joint?

Yes. Rotary joints with singlemode fibre channels at 1310/1550 nm are available, often combined with slip ring ways for power and control.

Sources

Engineer support

Get your products sourced with UK engineering support

Tell us the part or application, quantity and timing. We connect your requirement with experienced UK engineering and procurement support for product selection, sourcing and pricing. Delivery and after-sales arrangements are confirmed by your chosen provider.

  • Reviewed by an engineer, not an autoresponder
  • Like-for-like and better-fit alternatives
  • Standard, modified and custom options

Prefer to configure it? Use the spec builder.

We use your details to answer this enquiry and share them with the specialist engineering and supply partner best placed to fulfil it. Read our introduction service terms and privacy notice.

UK engineering input · A route to buying the right products

From your enquiry to products, delivery and support

Specify Motion helps turn a part number or application into a purchasing enquiry. We provide recommendations and connect your requirement with a relevant engineering or procurement provider for product selection, pricing, sourcing and supply.

  1. Tell us what you needSend a code or configure the application, quantities and timing.
  2. Reach a relevant providerAccess experienced UK engineering input and a suitable procurement route.
  3. Review the quotationYour provider confirms the products, price, compatibility checks and supply terms.
  4. Order with delivery and support agreedConfirm delivery, warranty and after-sales arrangements with the contracting provider.
Get pricing and sourcing support →Use the full configurator

You choose whether to proceed with the provider and should carry out your own checks. Website and introduction service terms.