A connector chosen by frequency alone can still fail the board it sits on. At 40, 67 and 110 GHz, the transition from PCB to coax is part of your circuit, so the launch should be selected with the board layout, not after it.

Southwest Microwave end-launch and vertical-launch connectors, available from HASCO, give RF PCB designers, hardware engineers and prototype teams a controlled transition to precision coax. This article covers three decisions that make the match work: how the launch meets your board, which interface fits your band, and how to assess the transition as a whole.

1. Start with layout and access: end launch or vertical launch?

Board access decides the launch geometry before frequency does. Both families transition planar circuitry to coax, so choose the one that fits where the connector can physically go.

• End-launch connectors mount at the board edge. Multiple block widths, profiles, transition sizes and thread-in configurations support evaluation boards, modules and reusable test hardware.
• Vertical-launch connectors mount through the board surface. They suit designs where edge access is unavailable or the launch has to sit within the PCB area. The compression-mount designs are removable and reusable.

Ask three questions early: Is the board edge available? Does the enclosure or fixture dictate where the coax exits? Will the connector stay on the board, or move between prototype revisions? Answering them first narrows the field before you open a datasheet.

Browse both families: end-launch connectors and vertical-launch connectors.

2. Match the interface to your band and mechanical needs

Once the geometry is set, pick the interface from the operating band and the mechanical requirements of the design. These vertical-launch models are representative starting points.

Frequency limits are model-specific. The 145 GHz test data applies to the 0.8mm vertical launch, and each end-launch and vertical-launch product carries its own published limits. Confirm coverage, drawing revision and current availability before you release the board.

Mechanical fit matters as much as band. End launches come in several block widths, profiles and transition sizes, and compression-mount vertical launches can be removed and reused, which helps when a design goes through several revisions.

3. Assess the complete transition, not just the connector

A launch performs only as well as the board around it. Substrate, stackup, trace width, copper geometry, vias and ground continuity all influence the result, so review them together with the connector.

• Stackup and substrate: confirm the board material and thickness against the connector drawing.
• Trace geometry: check the transmission-line structure the launch will feed, such as microstrip or grounded coplanar waveguide.
• Grounding: keep ground continuity and via placement in view as part of the footprint.
• Installation: plan how the connector is attached and removed, especially if the board will be reworked or reused.

Before fabrication, work from the applicable drawing, the recommended footprint, simulations and published test data. Catching a footprint or stackup mismatch at layout costs far less than a board respin.

Request a quote and selection support

Share your board details and HASCO can help match the launch to your design, from connector selection through procurement. Include:

• Operating band
• Board stackup, including PCB material, trace geometry and board thickness
• Launch configuration: end launch or vertical launch
• Interface requirements
• Quantity and required schedule

Request a quote, call 888-498-3242, or email sales@hasco-inc.com. To compare the full range first, see the Southwest Microwave end- and vertical-launch connector page.