Posts Tagged ‘10dbi’

Sector Antenna GRAD2487

Friday, September 28th, 2007

This is interesting russian antenna. Small sector antenna, gain is only 10 to 12 dbi.

Sector Antenna GRAD2487

From this site I can find that the price of this is nearly 200 euros or 260$ !!!

Quick specifications :

Frequency band   2400-2483 MHz
Gain   13 dBi
Maximum input power   100 W
Power distribution diagram  
  • Horizontal: 90°;
  • Vertical: 18°;
Impedance   50 Ohm
Standing wave coefficient   1,5
Mast mount diameter   35-60 mm
Weight   1.8 kg
Size, L x W x H   250x160x360 mm
Maximum wind speed   160 km/h
Polarization   Vertical
Operating temperatures   -40° … +50° C
Connector   N-Type female
Additional information   Input is DC-circuited

In the russian forums for a lot of antennas this last “Input is DC-circuited” is very critical ! There is some sort of fanaticism about this 🙂 may be the weather there, I’m not sure why.

Here is link to some pictures of the interior from here :


What we have under the fiberglass hood – strong plate which hold connector, coax line to the one pcb plate whit four printed dipoles.

The design of the dipoles is very interesting to me – I sow this dipole design several times :


You can find dimensions of this antenna whit lot of pictures forum.

I’m not completely sure why this antenna is so interesting to me.

You can search in google for “printed Dipole Antenna with integrated Balun” and will find something very similar to the upper pictures. So design is well known and used from manufacturers.

Here some links :

printed_dipole_design2_600_396.jpg printed dipoleprinted dipoleprinted dipole

On these examples balun is madded whit hole trough the plate or “via hole” , but on this antenna we do not have a hole.

BUT without this hole I cannot see this “Input is DC-circuited” thing! Where they close the loop?

Here I find something very similar only multiplied by four for creating omnidirectional antenna :


And finally one more picture on which we have similar dipole and feeding :


For final this is very complicated antenna extreme hard to be reproduced without proper materials, equipment and software tools.

This shows very professional design whit a lot of variables and places which need to be tunned. For me this antenna is impossible to be built at home.