This procedure applies to twin LNBs of the Golden Media type. DC supply and the intermediate frequency are routed through one F connector, while the LO reference is fed in through the second connector. The modification is outlined in the schematic below.

Procedure

1. Open the LNB and remove the silicone sealant.
2. Power the LNB with 12 V and probe the crystal oscillator with a scope – it can also sit on the opposite side of the PCB. Find the pin that shows the highest level.
3. Remove the oscillator and the capacitors (Cs) at that pin, using a hot air gun or two soldering irons.
4. At the LO connector, remove the printed inductor (PCB-L) and the capacitor to the mixer.
5. Freely position the resistors (Rs) and capacitors (Cs) from the LO connector to the free oscillator pad. Different LNB versions need different routings. Use tape to isolate PCB tracks.
6. At the intermediate frequency connector, remove the printed inductor (PCB-L) and replace it with a 2.2–4.7 µH ferrite bead. Make sure the ferrite bead’s resonance frequency is far away from 400–800 MHz.
7. Test with an external power supply and LO. Current consumption should be 100–120 mA.

Photos

Courtesy of DL9SBY