Pencil test as it applies to Mesh C-Band

[Inno]

When people talk about taking a number 2 pencil and if it passes through the holes in the mesh to tell if your C-band will work for Ku, do they mean just the lead of the pencil? I'm guessing yes as they wouldn't specify a number 2 pencil if it were the whole shaft of the pencil.

I guess what I'm really asking is, what is the maximum acceptable diameter of hole in the mesh that will still work for Ku?

 

[tdti1]

I think it's the whole pencil? I know my warped big hole mesh dish gets ku-band pretty good, well when it's aligned need to do that one day

 

[Azel]

I'd have to look up the author . In his design, he said the holes need to be less than 1/10th wavelength in diameter. That works out to 0.1 inch (12 GHz).

 

[linuxman]

On my Birdview dish the holes are just shy of the whole shaft of a number 2 pencil and it gets the best Ku signal of any dish I own including all my primestars.

Our own Caddata has stated many times that the hole size only needs to be smaller than .250" to work for Ku.

The surface accuracy and the parablic shape are more important than the size of the holes.

Fred

 

[Diamond Jim]

I've always assumed that it meant the whole pencil. Since I am solid, I've never had to deal with it.

 

[Tom Taylor]

The measurement we used to use was a #40 drill bit, .098 inches. Other things like a lot of "Flat" metal between the holes can also reflect Ku signals, thus some of the old dishes that looked like a spun or formed dish might work even though the holes were quite large. Quality of dish is important, the curve must be more accurate for Ku thus old Prime Star dishes may our perform some 10 foot mesh dishes.

 

[Inno]

Great, thanks for all the answers. I have so far located 3 dishes thru a free ad I put in a local paper, one of which I have worked on but I can't remember the details of it. The other two (which I got a call about last night) aren't far from here so I'll likely go and look at them over the weekend, the guy says they are in good shape, one is all together, the other one is apart. He used to use them for the Outdoor channel until it went digital..........hmmm, perhaps we have a potential satellite guy on our hands, he wasn't aware you could connect a FTA receiver to a BUD. It seems like the majority of the world (or at least our continent) thinks that FTA is something you use to steal signal.