A window feed-through (window pass-through) lets you bring coax and a ground into your station without drilling. When installed well, it also keeps the window insulated and secure. This guide shows a clean install using a Micro Patch feed-through and Window Wing Kit from Rocket Machine Worx (not sponsored), plus tips that apply to most similar products.

 

Materials & Tools

Item Notes
Window feed-through (e.g., Micro Patch) Stainless center plate + 3× SO-239 bulkhead connectors
Window Wing Kit 2× marine-grade HDPE wings, gaskets, anti-seize, bolts
10 AWG green grounding wire Crimp lugs & stainless hardware
⅜″ foam weather-strip & seal tape Improve insulation and draft control
Window lock bars (10″–16″) Apply pressure; add security
Optional lightning arrestors Install near the ground rod outdoors
Tools Tape measure, square/triangle, marker, hacksaw, file, wire strippers, driver/wrench
Window feed-through kit unboxed: stainless center plate, HDPE wings, gaskets, bolts.
Unboxed window pass-through kit with stainless center plate, HDPE wings, gaskets, and hardware.

Where to Buy the Window Feed-Through Parts

Not sponsored—these are the exact parts used in our build.

Unbox & Inspect

Confirm the contents: the stainless center unit with coax connectors, two HDPE wings, gaskets, and four bolts. Dry-fit the parts to make sure threads and holes line up cleanly.

Testing the feed-through position and closing the sash to check clearances.
Dry-fitting the pass-through panel to confirm placement and sash compression before cutting.

Measure the Window

Windows have grooves and ridges. Measure the exact opening width where the panel will sit. Close the window gently to see how the sash compresses the wings. Cutting too short creates gaps; slightly long is easy to file.

Assemble the Panel

Apply the included anti-seize to the wing bolts. Thread the bolts into the stainless center plate. Slide on the gaskets to create an insulation layer, then press the HDPE wings onto the bolts.

Anti-seize on bolts with gasket between center plate and HDPE wing.
Apply anti-seize and add the rubber gasket between the center plate and HDPE wing for better insulation.

Cut to Length

Mark the wing with a pen. Use a square to draw a straight line, then cut with a hacksaw. Cut a little long, then file to a snug fit. Leave space for weather-strip at both ends.

Marking and cutting the HDPE wing to length with a hacksaw.
Measure, mark with a square, and cut slightly long—then file to a precise fit.

Add Weather-Seal

Apply ⅜″ foam weather-strip around all four sides of the panel. This improves the air seal and keeps the shack comfortable year-round.

Foam weather-strip applied around the perimeter of the panel.
Foam weather-strip around all edges boosts the pass-through’s insulation and seal.

Test-Fit & Adjust

Seat the panel and close the sash. If it’s too tight, file a touch more. If gaps appear, add foam or thin shims. In a pinch, a small wood shim works.

Attach Ground & Coax

Crimp a lug on 10 AWG green wire and bond it to the feed-through ground with stainless hardware. Route the wire to your station ground. Connect PL-259 coax jumpers. If you use lightning arrestors, place them near the ground rod outdoors.

Installed feed-through with coax jumpers and 10 AWG green ground wire.
Completed no-drill installation with bonded ground and coax routed through the window.

Finish & Secure

Add a strain-relief eye hook for heavier coax (e.g., RG-8). Use window lock bars to apply pressure and improve the seal. Fill tiny gaps with seal tape. Now connect the indoor coax to your radio and enjoy operating on VHF/UHF and HF—no holes required.

Completed ham radio window feed-through panel under the sash with sealed edges, ready for strain-relief, lock bars, and final coax hookup.
Finished window pass-through—add a strain-relief eye hook, set window lock bars for compression, seal gaps, and connect your indoor coax.


Safety & RF Note: Always follow local codes and best practices for grounding and bonding. For RF exposure guidance, see the FCC’s page on Radio Frequency Safety.

Learn more antennas: See our guide to Ham Radio Antennas and our HF for Beginners article.

Go Further: Satellite & Space Operations

Ready to expand your station skills? Decode satellites, track passes, and build portable antennas with guided labs.
Enroll in Satellite & Space Operations
 

FAQs

Do I need to drill any holes?
No. A window feed-through provides a solid, removable path for coax and ground without drilling your wall.
Will this keep my room insulated?
Yes—use the included gaskets and add ⅜″ weather-strip around the perimeter. Window lock bars improve the seal even more.
Where should I install lightning arrestors?
Outdoors near the ground rod, not indoors. Bond the arrestors to your station ground.
What if I cut a wing too short?
Use a thin shim temporarily, but the best fix is a replacement wing. Cutting slightly long and filing is safer.