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What is difference between 90 deg vs 100 deg couplers when driving mixer diodes?

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Terminator3

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I am looking at these pictures:
1) Single balanced mixer based on branchline coupler (90 deg):
https://www.qsl.net/va3iul/Homebrew...e_Single-Balanced_Narrowband_Hybrid_Mixer.gif
2) 180 degree hybrid:
https://www.microwaves101.com/encyclopedias/hybrid-couplers
and here on page 5:
https://www.jpier.org/PIER/pier.php?paper=11022109
As shown in Fig. 2, the LO signal is applied to
port 1, so the LO voltage has 180 degrees phase difference at the input
of the two diodes. However the two diodes are reversed, then the LO
signal is in-phase to the diodes.
But when we using 90-degree coupler, it seems that diodes will be driven differently, as phase difference is not 180 degree? For example, in 180 deg hybrid diodes will be "switched" by LO each 180 deg (180+180=360 deg)
In case of branchline 90-deg coupler, diodes will be switched in "bursts" each 270 deg. (270+90=360deg). I hope someone understand my confusion and lead me in right direction.
 

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