Mi-Wave · Waveguide Flange Adapters
688 Series Flange Adapters
Precision-machined flange-to-flange adapters for 8 GHz to 60 GHz waveguide systems
The Mi-Wave 688 Series is a short, precision-machined waveguide section with a different flange on each end, covering 8 GHz to 60 GHz in standard waveguide sizes. It exists for the moment when the Ku, K, Ka, Q or U band component you have bought carries a flange your system does not. Controlled bore dimensions and no surface discontinuities keep insertion loss and VSWR low, so the adapter can stay in the line. Evencat is an authorized Mi-Wave distributor in Taiwan.
Overview
The 688 Series runs from Ku-band (12.4 GHz) to U-band (60 GHz) in nine catalog combinations built around the UG-419, UG-541, UG-595, UG-425, UG-596, UG-381, UG-599, UG-600, UG-383, UG-385, UG-719 and UG-720 flange families. Each adapter is machined so the waveguide bore is held to size end to end, which removes the steps that would otherwise cause reflection and loss in the transmission line. The parts are used in mm-wave communications, radar, satellite, aerospace and defense builds wherever components or sub-assemblies from different vendors have to be joined. Beyond the catalog list, Mi-Wave makes adapters to order for any flange pair described by its Appendix A flange codes. Before you order, check both flange faces against the mating hardware, including whether the flange is the plain or the -M variant, and note that every catalog part is 1.00 in long.
Key specifications
| Frequency coverage | 8 GHz – 60 GHz |
|---|---|
| Bands | Ku-Band (12.4–18 GHz), K-Band (18–26.5 GHz), Ka-Band (26.5–40 GHz), Q-Band (33–50 GHz), U-Band (40–60 GHz) |
| Standard length | 1.00 in (25.40 mm) |
| Ku-Band model 688KU/419/541 | Flange A: UG-419/U; flange B: UG-541/U; weight 3.0 oz |
| K-Band model 688K/595/596 | Flange A: UG-595/U; flange B: UG-596/U; weight 1.3 oz |
| K-Band model 688K/595/425 | Flange A: UG-595/U; flange B: UG-425/U; weight 1.4 oz |
| Ka-Band model 688A/381/599 | Flange A: UG-381/U; flange B: UG-599/U; weight 1.2 oz |
| Ka-Band model 688A/381/600 | Flange A: UG-381/U; flange B: UG-600/U; weight 1.1 oz |
| Ka-Band model 688A/599/600 | Flange A: UG-599/U; flange B: UG-600/U; weight 1.1 oz |
| Q-Band model 688B/383/385 | Flange A: UG-383/U; flange B: UG-385/U; weight 0.8 oz |
| Q-Band model 688B/383/719 | Flange A: UG-383/U; flange B: 719; weight 0.8 oz |
| U-Band model 688U/383/720 | Flange A: UG-383/U; flange B: 720; weight 0.8 oz |
Features
Precision-machined body
Each adapter is machined with the bore held to size and no surface steps, which is what keeps loss and VSWR low at mm-wave frequencies.
8 to 60 GHz coverage
One series covers Ku, K, Ka, Q and U bands, so most flange mismatches between 8 GHz and 60 GHz are solved from stock.
Nine flange combinations
Catalog parts pair UG-419/U, UG-541/U, UG-595/U, UG-425/U, UG-596/U, UG-381/U, UG-599/U, UG-600/U, UG-383/U, UG-385/U, 719 and 720 flanges in the combinations engineers meet most often.
One common length
Every catalog adapter is 1.00 in (25.40 mm) long, which makes mechanical layout predictable across a multi-band build.
Custom flange pairs
Beyond the catalog, Mi-Wave designs and machines adapters for non-standard flange pairs when a system needs an interface that does not exist off the shelf.
Interface between sub-systems
The 688 Series joins components and sub-assemblies with different flange standards in satellite, aerospace, defense and communications test equipment.
Typical applications
Measurement and calibration
VNA calibration and component measurement
For S-parameter work between 8 and 60 GHz, a 688 Series adapter sits between the frequency extender and the DUT to reconcile flange standards such as UG-383, UG-387 or CPR. The machined bore has no steps, so the loss and VSWR each connection adds stay small and the TRL reference plane holds.
Satellite and aerospace
Joining sub-systems in ground stations and airborne radar
When a Ka-band (26.5–40 GHz) earth station or an airborne phased array is assembled, the feed, LNA and converter often arrive from different vendors with different flanges. A 688 adapter bridges them, keeps the link intact under high power and meets the mechanical stability that aerospace hardware requires.
R&D lab
Prototyping mm-wave modules quickly
Engineers building 5G mm-wave, automotive radar or imaging prototypes regularly find the lab instruments and the new module do not share a flange. With a 688 adapter in the catalog combination they need, they connect fixtures of different waveguide standards without machining a custom jig, which shortens the design-to-measurement loop.
Options and configuration
Tick the band and flange pair you need; the selections are collected into a list and carried into the quote form.
Band
Flange pair
Downloads
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