I have a used version of the subject antenna, which is still quite operational. However, I recently needed either a way to tie into reception from this antenna or purchase additional antennas. Given the cost of active patch antennas, I tried one from Adafruit.
While comparing reception on a Trimble Thunderbolt to an integrated GPS module (used for time and PPS on a WSPR transmitter) is not apples to apples, I did notice how many more fixes the latter receiver obtains. For example, when the Thunderbolt has fixes on 6 birds, the YIC51612 (MediaTek) receiver module will have 10. I am sure the criteria is not the same for what constitutes a fix in both cases, but I also observed the following. By simply using a 0.1 uF SMD MLCC cap to couple into the Trimble Bullet, i.e. the Thunderbolt still powers the amp with +5v, but the signal has a path to my other GPS receiver, the bullet antenna underperformed by a significant amount. What's possibly worse is that the patch antenna is on a window sill, whereas the bullet antenna is on the roof with a clear view of the sky. I have not tried the Adafruit patch with the Thunderbolt yet as I will have to reduce the LNA voltage from 5 to 3.3 before trying the second test. The general question I wanted to ask though is what others use/like as roof mounted antennas? Are some of the 'Marine' antennas better? Russ K0WFS _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
