When I search for WR650 waveguides, I get results for 12-26GHz rather than correct wavelengths that cover 1.4GHz. Why is that?
It happens because “WR-650” means two completely different things depending on context, and most search engines don’t know which one you want.
1. The actual WR-650 (large waveguide) is for 1.12–1.70 GHz
In standard rectangular waveguide nomenclature,
WR-650 → 6.50 in × 3.25 in internal size, which supports:
- TE₁₀ cutoff ≈ 0.91 GHz
- Recommended operating band ≈ 1.12–1.70 GHz
That covers the 1.420 GHz hydrogen line, and this is the correct waveguide for your 1420 MHz feed design.
This enormous waveguide is common in UHF radar, L-band radio astronomy, and high-power broadcast/military systems.
2. Search engines often rewrite “WR650” as “WR-65” or “WR-62”
Unfortunately:
- WR-65 is a tiny waveguide for 18–26.5 GHz (millimetre wave)
- WR-62 is for 12.4–18 GHz
When you type WR650, many shopping/catalog algorithms incorrectly assume you meant WR65, because:
- WR-650 is rare and expensive
- WR-65 is common in commercial microwave/mm-wave components
- Most vendors index their products by short WR numbers (WR10, WR28, WR62, WR75, WR90, etc.)
So the search engine “autocorrects” your request and drowns the real WR-650 results under a pile of mm-wave hardware.
3. How to get the correct results
Try searching explicitly with:
- “WR-650 L-band waveguide”
- “WR650 1.12–1.70 GHz”
- “L-band rectangular waveguide 6.50 inch”
- “R14 waveguide” (military/NATO designation for WR-650)
Suppliers that actually list WR-650 include Mega Industries, Microwave Engineering Corp, L-3 Narda-Miteq, and some surplus RF and radar parts dealers.