Gauge and millimeters conversion

[RicoBangBang 0]

Hello,

I should soon try to make a 910 mhz antenna but I have a doubt about the galvanized metal sheet thickness.

A 24 gauge should be 0.7010 mm and a 30 gauge should be 0.3988 mm. Am I right ?

[Mr.RC-Cam 123]

If you are building a 900MHz patch antenna then select a sheet metal gauge that will hold its shape with the expected field abuse, but is not so heavy it is impractical to mount on a stand. FWIW, both 24 gauge and 30 gauge seem a bit flimsy for a big 900MHz patch.

[RicoBangBang 0]

Thank you for the reply. What gauge would you advise for this 900 mhz antenna ?

[Mr.RC-Cam 123]

The 900MHz patch is BIG. So the lightweight sheet metal choices that are good for smaller patch antennas are not appropriate for this big boy.

Regarding the gauge you should use: I'm a touchy-feely guy. I go to the hardware store and handle the sheet metal on the shelf. I select the sample that feels stiff enough for the job (it has to retain its flat shape with all the rough handling to/from the field).

[RicoBangBang 0]

You are right, I think I would use a 1 mm thick galvanized sheet. I have found a tilt shift mount at this address and think it should move the antenna if I put the appropriate servos.

[RicoBangBang 0]

I have only found 2 mm galvanized steel sheet. Does the thickness have consequences on the antenna quality ?

[Mr.RC-Cam 123]

On common antennas (monopoles, dipoles, etc) the RF bandwidth is affected by the element thickness (diameter). But on a 900MHz patch I would not expect any practical impact to RF performance if you used 2mm thick material.

[RicoBangBang 0]

Thanks. I will therefore use 2 mm thick material and will let you wether there are side effects.