Low noise block PCB mounting system using non-linear insertable probes
View Patent ↗A low nosie block (LNB) system is described which facilitates the mount of printed circuit board (PCBs) with probes attached to an LNB housing. The LNB housing has, in a preferred arrangement, two keyhole-shaped apertures located in the back wall of the waveguide for receiving the probes already mounted to the PCB. The apertures are dimensioned and proportioned to lie on either side of a waveguide septum and to allow probes, when coupled to a printed circuit board, to be inserted through the respective apertures for correct orientation within the waveguide once the printed circuit board is secured to the housing and to allow minimal transmission of electromagnetic radiation through the apertures other than by a transmission line formed by the probes.
1. A low noise block (LNB) having an antenna feed, a waveguide coupled to the antenna feed, the waveguide having a rear wall, a housing coupled to the waveguide and arranged substantially perpendicular to the waveguide, the waveguide rear wall comprising a part of the housing, the waveguide rear wall having at least one aperture therein for receiving a non-linear probe when coupled to a printed circuit board, the at least one aperture being dimensioned to allow the non-linear probe coupled to a printed circuit board to pass through the waveguide rear wall and into the waveguide such that the non-linear probe is oriented in the waveguide for reception of electromagnetic radiation passing therealong, said at least one aperture having dimensions being proportioned to minimise the leakage of microwave radiation passing through the aperture other than by the non-linear probe, the printed circuit board being insertable and removable with respect to the LNB housing without decoupling the printed circuit board from the non-linear probe.
2. A low noise block as claimed in claim 1 wherein said at least one aperture comprises two apertures disposed in the rear wall of the waveguide.
3. A low noise block as claimed in claim 2 wherein the two apertures are arranged on either side of a waveguide septum for receiving a respective probe on either side of the septum.
4. A low noise block as claimed in claim 3 wherein the two apertures are elongate.
5. A low noise block as claimed in claim 3 wherein the two apertures are keyhole-shaped and have ends which converge towards the septum of the waveguide.
6. A low noise block as claimed in claim 3 wherein the two apertures are rectangular, oval or circular.
7. A low noise block as claimed in claim 2 wherein the two apertures are rectangular, oval or circular.
8. A low noise block as claimed in claim 2 wherein the two apertures are elongate.
9. A low noise block as claimed in claim 2 wherein two the apertures are keyhole-shaped and have ends which converge towards each other and towards a septum of the waveguide.
10. A low noise block comprising an antenna feed, a waveguide coupled to the antenna, said waveguide having a rear waveguide wall, a housing coupled to the waveguide, wherein the rear waveguide wall comprises part of the housing, and the housing being oriented substantially perpendicular to the waveguide, a printed circuit board adapted to be secured to the housing, the printed circuit board carrying two non-linear probes for insertion into the waveguide, said rear waveguide wall having two apertures disposed therein for respectively allowing said non-linear probes when coupled to the printed circuit board to pass through the waveguide rear wall and into the waveguide, said apertures having dimensions being proportioned to receive said non-linear probes without the probes being removed or separated from the printed circuit board for installation of the non-linear probes within the waveguide and for removal of the non-linear probes from the waveguide.