On Tue, 6 Feb 2018 07:08:42 -0600 John Green <wpxs...@gmail.com> wrote:
> Thanks for the responses. It looks similar to but not exactly like the two > antennas referenced. They say the preamp is 3 to 5.5 volts, whereas the > eBay antenna says its preamp is good from 3.3 to 18 volts, indicating I can > run it off 12 volts. I am pretty sure that this is either a mistake or a deliberate deceit. Most LNA's I am aware of work between 3.3V and 5V. The cheap ones are definitely all in that range. Some of those might work for a short time with higher voltage, depending on the actual semiconductor process used for production. But that means using those chips outside their specs and putting a high straign on the semiconductor, which will lead to an early death. It also cannot be an LDO inside the antenna, as 3.3V is pretty much the lowest voltage you can get an LNA for. There are some that work at 3.0V still, but that would leave only 0.3V for the LDO, which requires a more expensive LDO. I am pretty sure there are some LNAs that work at 2.5V or even lower, but those would be definitely in the way-too-expensive category. So, my guess is, they tested the antenna whether it works with 12V, seen that it does, and just "adjusted" the specs. But in reality, the LNA still maxes out at 5V if you want a reliable device. Attila Kinali -- <JaberWorky> The bad part of Zurich is where the degenerates throw DARK chocolate at you. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.