I connected my new M2 to an old Leica GS20 antenna I have here.
The result was surprising.
Took a lot of satellites and fixed it as my RS2.
I did the test with Ntrip and with LoRA as well.
These Emlid components surprise me more and more every day.
I thought a 2003 antenna (almost 20 years old) wouldn’t give me such good results.
Have in mind that while this might work, your signal quality on the L2 band will suffer (a lot) as compared to using an antenna that is tuned to also receive L2.
An L1-only antenna is basically tuned for 1570-ish mhz, whereas L2 is rougly 12xx mhz.