Surprisingly little better than my home made resistive splitter (three 51 ohm resistors wired in delta) with regard to splitting the GPS antenna feed out to two GPSDOs. For this use, I'd had to cut a 1mm break in the circuit trace right at one of the two sockets to insert a chip capacitor to DC block the 3.3v antenna power feed to stop the receiver modules fighting each other. I'd used the same modification in the resistive splitter effectively levelling the playing field for this comparison. The effective 33 ohms in series with the 3.3v feed from the other GPS receiver providing antenna power only drops a mere 264mV at the 8mA current drawn by the active antenna, leaving ample voltage to power its LNA. The modified power splitter/combiner incurs no such volt drop which is a bonus when used with active antennas requiring much more current which could be as much as 100mA in the case of extended antenna feeds requiring a line powered LNA repeater or two in addition to the one in the active antenna.

Surprisingly little better than my home made resistive splitter (three 51 ohm resistors wired in delta) with regard to splitting the GPS antenna feed out to two GPSDOs. For this use, I'd had to cut a 1mm break in the circuit trace right at one of the two sockets to insert a chip capacitor to DC block the 3.3v antenna power feed to stop the receiver modules fighting each other. I'd used the same modification in the resistive splitter effectively levelling the playing field for this comparison. The effective 33 ohms in series with the 3.3v feed from the other GPS receiver providing antenna power only drops a mere 264mV at the 8mA current drawn by the active antenna, leaving ample voltage to power its LNA. The modified power splitter/combiner incurs no such volt drop which is a bonus when used with active antennas requiring much more current which could be as much as 100mA in the case of extended antenna feeds requiring a line powered LNA repeater or two in addition to the one in the active antenna.

Surprisingly little better than my home made resistive splitter (three 51 ohm resistors wired in delta) with regard to splitting the GPS antenna feed out to two GPSDOs. For this use, I'd had to cut a 1mm break in the circuit trace right at one of the two sockets to insert a chip capacitor to DC block the 3.3v antenna power feed to stop the receiver modules fighting each other. I'd used the same modification in the resistive splitter effectively levelling the playing field for this comparison. The effective 33 ohms in series with the 3.3v feed from the other GPS receiver providing antenna power only drops a mere 264mV at the 8mA current drawn by the active antenna, leaving ample voltage to power its LNA. The modified power splitter/combiner incurs no such volt drop which is a bonus when used with active antennas requiring much more current which could be as much as 100mA in the case of extended antenna feeds requiring a line powered LNA repeater or two in addition to the one in the active antenna.