WR-1150 or WR-1000 wg to coax adapter?
WR-1150 or WR-1000 wg to coax adapter?
(OP)
Anyone out there have approximate dimensions for a WR-1150 or WR-1000 waveguide to coax adapter? My empirical attempts have been coming out with pretty poor VSWRs!
www.MaguffinMicrowave.com
Maguffin Microwave wireless design consulting





RE: WR-1150 or WR-1000 wg to coax adapter?
11.5"x5.75" inside dimensions tolerance 0.015"
11.75"x6" outside dimensions tolerance 0.015"
0.125" wall thickness.
wr975 or wr1500 are my other two items around the wr1150.
RE: WR-1150 or WR-1000 wg to coax adapter?
1) Backshort position
2) Efield proble length
3) Efield probe diameter
4) any tuning screw locations
www.MaguffinMicrowave.com
Maguffin Microwave wireless design consulting
RE: WR-1150 or WR-1000 wg to coax adapter?
www.MaguffinMicrowave.com
Maguffin Microwave wireless design consulting
RE: WR-1150 or WR-1000 wg to coax adapter?
I expect you may have done this already, so at the risk of seeming obvious, I'd expect you could take a standard waveguide to coax transition like this one http://www.pasternack.com/Pdf/PE9825.pdf which gives the distance from the coax to the back wall and frequency scale it.
Then make the probe flare outward at various angles and add tuning screws or two at the bottom? If you've tried to use a straight probe, I'd guess a flared probe would be better. You could make the flare an X shaped brass shim stock soldered to the type N probe center conductor.
I have a feeling you've tried that. So maybe I'm asking what you've tried already out of curiousity.
kch
RE: WR-1150 or WR-1000 wg to coax adapter?
One thing that I noticed in the wg-coax transitions I have lying around the lab is that they use a larger diameter slug at the end of the efield probe. I would assume that is to better match the vswr. Does the diameter of that slug increase with linear to the waveguide width dimension?
www.MaguffinMicrowave.com
Maguffin Microwave wireless design consulting
RE: WR-1150 or WR-1000 wg to coax adapter?
I'm not used to seeing a large diam. stub, usually 3 tuning screws on the bottom, although some have none.
If I were making this, I'd get the waveguide, make a tunable short in the back, buy a type N-f to N-f bulkhead adapter. Stick it in the waveguide with a probe pin attached to the inside N-f, and add a copper or silver metal tape triangle to the probe and shape that. For a more permanent pin, you could use either a thin copper clad circuit card (FR4) or shim stock and solder it onto the probe. It might be better to have a real probe machined though.
Seal the probe in the N-f. Then maybe add tuning screws for fine tune on the bottom under the probe to tweak the final assy. You could add a large tuning screw to that formerly movable back wall too for a little extra control.
This all depends on power requirements of course.
If you're going to make alot of these, hire a consultant to fine tune your design and avoid tuning screws.
We use Jim Reed at optimal designs in Austin Texas to fine tune your design on CST and skip all the tuning screws and movable walls. Probably cost $5K ish. We use Jim alot, good Engineer and I wish he'd start paying me for recommending him.
kch