[NLRS] 10 GHz antenna needed

[Dr. Gerald N. Johnson]

I believe W6DFW is a silent key now. That was mentioned in the SBMS 
newsletter several months ago.

There is a Danish source, probably not cheap.
www.procom.dk/products/microwave-antennas/10-ghz/omnidirectional-antennas/wgsl-10

I have a vertical mill, but too many projects though I'd like to put up 
a 10 GHz beacon too, about half way to the cities. I'm considering 
cutting the slots with a circular saw instead of a small endmill to get 
a much better cut and without breaking small end mills from cranking the 
table too fast in gummy copper. I have hundreds of 3 and 4" diameter 
metal cutting saw blades. But I don't know the effects at the ends of 
the slots being a different length at the inside and outside of the 
guide wall. Or having square ends instead of round ends. I suppose I 
could cut most of the slot length with a small saw blade (1" diameter or 
less) and then finish the ends with the end mill to make them rounded as 
most are planned to be with the inside and outside lengths the same. 
Slots could be made by drilling a series of holes and connecting them 
with needle files.

There is a design program at W1GHZ web site that has been proven to be 
good for round ended slots.

There is considerable experience that using standard height wave guide 
results in an antenna with considerable ripple in the azimuth pattern. 
One solution pushed by Kent Britain is a pair of wings to widen the 
radiating surface. I have also found literature that says lowering the 
guide height is another solution. Indeed etching slots in a double sided 
circuit board with a pile of vias to make a dielectric filled waveguide 
shows good circularity. I think it might do OK to just cut the board to 
the guide width and then use copper tape to close it more solidly than 
the gang of vias, though maybe the wider circuit board beyond the guide 
is acting like Kent's wings on standard copper guide. I have a lot more 
literature to read on that topic.

73, Jerry, K0CQ

On 7/29/2015 8:49 PM, Arliss wrote:
>
>
> Hi,
>
> I'm working on putting a 10 GHz beacon on the air. I need an
> omni-directional antenna, such as a slot antenna. I'm wondering if
> anyone can suggest a source for one of these?
>
> Pyro-Joe has some 24 GHz slot antennas on eBay, but I didn't find any 10
> GHz models. I emailed him asking about a 10 GHz version, but haven't
> heard back from him yet.
>
> I also emailed W6DFW, who at one time manufactured these antennas and
> was, I believe, associated with SBMS. However, I haven't heard back from
> him, either.
>
> Any leads would be appreciated.
>
>
> 73, Arliss W7XU
>
>